2 * Copyright (c) 2016-2019 Cisco and/or its affiliates.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at:
7 * http://www.apache.org/licenses/LICENSE-2.0
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
16 #include <vppinfra/sparse_vec.h>
17 #include <vnet/tcp/tcp_packet.h>
18 #include <vnet/tcp/tcp.h>
19 #include <vnet/session/session.h>
22 static char *tcp_error_strings[] = {
23 #define tcp_error(n,s) s,
24 #include <vnet/tcp/tcp_error.def>
28 /* All TCP nodes have the same outgoing arcs */
29 #define foreach_tcp_state_next \
30 _ (DROP4, "ip4-drop") \
31 _ (DROP6, "ip6-drop") \
32 _ (TCP4_OUTPUT, "tcp4-output") \
33 _ (TCP6_OUTPUT, "tcp6-output")
35 typedef enum _tcp_established_next
37 #define _(s,n) TCP_ESTABLISHED_NEXT_##s,
38 foreach_tcp_state_next
40 TCP_ESTABLISHED_N_NEXT,
41 } tcp_established_next_t;
43 typedef enum _tcp_rcv_process_next
45 #define _(s,n) TCP_RCV_PROCESS_NEXT_##s,
46 foreach_tcp_state_next
48 TCP_RCV_PROCESS_N_NEXT,
49 } tcp_rcv_process_next_t;
51 typedef enum _tcp_syn_sent_next
53 #define _(s,n) TCP_SYN_SENT_NEXT_##s,
54 foreach_tcp_state_next
57 } tcp_syn_sent_next_t;
59 typedef enum _tcp_listen_next
61 #define _(s,n) TCP_LISTEN_NEXT_##s,
62 foreach_tcp_state_next
67 /* Generic, state independent indices */
68 typedef enum _tcp_state_next
70 #define _(s,n) TCP_NEXT_##s,
71 foreach_tcp_state_next
76 #define tcp_next_output(is_ip4) (is_ip4 ? TCP_NEXT_TCP4_OUTPUT \
77 : TCP_NEXT_TCP6_OUTPUT)
79 #define tcp_next_drop(is_ip4) (is_ip4 ? TCP_NEXT_DROP4 \
83 * Validate segment sequence number. As per RFC793:
85 * Segment Receive Test
87 * ------- ------- -------------------------------------------
88 * 0 0 SEG.SEQ = RCV.NXT
89 * 0 >0 RCV.NXT =< SEG.SEQ < RCV.NXT+RCV.WND
91 * >0 >0 RCV.NXT =< SEG.SEQ < RCV.NXT+RCV.WND
92 * or RCV.NXT =< SEG.SEQ+SEG.LEN-1 < RCV.NXT+RCV.WND
94 * This ultimately consists in checking if segment falls within the window.
95 * The one important difference compared to RFC793 is that we use rcv_las,
96 * or the rcv_nxt at last ack sent instead of rcv_nxt since that's the
97 * peer's reference when computing our receive window.
100 * seq_leq (end_seq, tc->rcv_las + tc->rcv_wnd) && seq_geq (seq, tc->rcv_las)
101 * however, is too strict when we have retransmits. Instead we just check that
102 * the seq is not beyond the right edge and that the end of the segment is not
103 * less than the left edge.
105 * N.B. rcv_nxt and rcv_wnd are both updated in this node if acks are sent, so
106 * use rcv_nxt in the right edge window test instead of rcv_las.
110 tcp_segment_in_rcv_wnd (tcp_connection_t * tc, u32 seq, u32 end_seq)
112 return (seq_geq (end_seq, tc->rcv_las)
113 && seq_leq (seq, tc->rcv_nxt + tc->rcv_wnd));
117 * Parse TCP header options.
119 * @param th TCP header
120 * @param to TCP options data structure to be populated
121 * @param is_syn set if packet is syn
122 * @return -1 if parsing failed
125 tcp_options_parse (tcp_header_t * th, tcp_options_t * to, u8 is_syn)
128 u8 opt_len, opts_len, kind;
132 opts_len = (tcp_doff (th) << 2) - sizeof (tcp_header_t);
133 data = (const u8 *) (th + 1);
135 /* Zero out all flags but those set in SYN */
136 to->flags &= (TCP_OPTS_FLAG_SACK_PERMITTED | TCP_OPTS_FLAG_WSCALE
137 | TCP_OPTS_FLAG_TSTAMP | TCP_OPTION_MSS);
139 for (; opts_len > 0; opts_len -= opt_len, data += opt_len)
143 /* Get options length */
144 if (kind == TCP_OPTION_EOL)
146 else if (kind == TCP_OPTION_NOOP)
158 /* weird option length */
159 if (opt_len < 2 || opt_len > opts_len)
169 if ((opt_len == TCP_OPTION_LEN_MSS) && tcp_syn (th))
171 to->flags |= TCP_OPTS_FLAG_MSS;
172 to->mss = clib_net_to_host_u16 (*(u16 *) (data + 2));
175 case TCP_OPTION_WINDOW_SCALE:
178 if ((opt_len == TCP_OPTION_LEN_WINDOW_SCALE) && tcp_syn (th))
180 to->flags |= TCP_OPTS_FLAG_WSCALE;
181 to->wscale = data[2];
182 if (to->wscale > TCP_MAX_WND_SCALE)
183 to->wscale = TCP_MAX_WND_SCALE;
186 case TCP_OPTION_TIMESTAMP:
188 to->flags |= TCP_OPTS_FLAG_TSTAMP;
189 if ((to->flags & TCP_OPTS_FLAG_TSTAMP)
190 && opt_len == TCP_OPTION_LEN_TIMESTAMP)
192 to->tsval = clib_net_to_host_u32 (*(u32 *) (data + 2));
193 to->tsecr = clib_net_to_host_u32 (*(u32 *) (data + 6));
196 case TCP_OPTION_SACK_PERMITTED:
199 if (opt_len == TCP_OPTION_LEN_SACK_PERMITTED && tcp_syn (th))
200 to->flags |= TCP_OPTS_FLAG_SACK_PERMITTED;
202 case TCP_OPTION_SACK_BLOCK:
203 /* If SACK permitted was not advertised or a SYN, break */
204 if ((to->flags & TCP_OPTS_FLAG_SACK_PERMITTED) == 0 || tcp_syn (th))
207 /* If too short or not correctly formatted, break */
208 if (opt_len < 10 || ((opt_len - 2) % TCP_OPTION_LEN_SACK_BLOCK))
211 to->flags |= TCP_OPTS_FLAG_SACK;
212 to->n_sack_blocks = (opt_len - 2) / TCP_OPTION_LEN_SACK_BLOCK;
213 vec_reset_length (to->sacks);
214 for (j = 0; j < to->n_sack_blocks; j++)
216 b.start = clib_net_to_host_u32 (*(u32 *) (data + 2 + 8 * j));
217 b.end = clib_net_to_host_u32 (*(u32 *) (data + 6 + 8 * j));
218 vec_add1 (to->sacks, b);
222 /* Nothing to see here */
230 * RFC1323: Check against wrapped sequence numbers (PAWS). If we have
231 * timestamp to echo and it's less than tsval_recent, drop segment
232 * but still send an ACK in order to retain TCP's mechanism for detecting
233 * and recovering from half-open connections
235 * Or at least that's what the theory says. It seems that this might not work
236 * very well with packet reordering and fast retransmit. XXX
239 tcp_segment_check_paws (tcp_connection_t * tc)
241 return tcp_opts_tstamp (&tc->rcv_opts)
242 && timestamp_lt (tc->rcv_opts.tsval, tc->tsval_recent);
246 * Update tsval recent
249 tcp_update_timestamp (tcp_connection_t * tc, u32 seq, u32 seq_end)
252 * RFC1323: If Last.ACK.sent falls within the range of sequence numbers
253 * of an incoming segment:
254 * SEG.SEQ <= Last.ACK.sent < SEG.SEQ + SEG.LEN
255 * then the TSval from the segment is copied to TS.Recent;
256 * otherwise, the TSval is ignored.
258 if (tcp_opts_tstamp (&tc->rcv_opts) && seq_leq (seq, tc->rcv_las)
259 && seq_leq (tc->rcv_las, seq_end))
261 ASSERT (timestamp_leq (tc->tsval_recent, tc->rcv_opts.tsval));
262 tc->tsval_recent = tc->rcv_opts.tsval;
263 tc->tsval_recent_age = tcp_time_now_w_thread (tc->c_thread_index);
268 * Validate incoming segment as per RFC793 p. 69 and RFC1323 p. 19
270 * It first verifies if segment has a wrapped sequence number (PAWS) and then
271 * does the processing associated to the first four steps (ignoring security
272 * and precedence): sequence number, rst bit and syn bit checks.
274 * @return 0 if segments passes validation.
277 tcp_segment_validate (tcp_worker_ctx_t * wrk, tcp_connection_t * tc0,
278 vlib_buffer_t * b0, tcp_header_t * th0, u32 * error0)
280 /* We could get a burst of RSTs interleaved with acks */
281 if (PREDICT_FALSE (tc0->state == TCP_STATE_CLOSED))
283 tcp_send_reset (tc0);
284 *error0 = TCP_ERROR_CONNECTION_CLOSED;
288 if (PREDICT_FALSE (!tcp_ack (th0) && !tcp_rst (th0) && !tcp_syn (th0)))
290 *error0 = TCP_ERROR_SEGMENT_INVALID;
294 if (PREDICT_FALSE (tcp_options_parse (th0, &tc0->rcv_opts, 0)))
296 *error0 = TCP_ERROR_OPTIONS;
300 if (PREDICT_FALSE (tcp_segment_check_paws (tc0)))
302 *error0 = TCP_ERROR_PAWS;
303 TCP_EVT (TCP_EVT_PAWS_FAIL, tc0, vnet_buffer (b0)->tcp.seq_number,
304 vnet_buffer (b0)->tcp.seq_end);
306 /* If it just so happens that a segment updates tsval_recent for a
307 * segment over 24 days old, invalidate tsval_recent. */
308 if (timestamp_lt (tc0->tsval_recent_age + TCP_PAWS_IDLE,
309 tcp_time_now_w_thread (tc0->c_thread_index)))
311 tc0->tsval_recent = tc0->rcv_opts.tsval;
312 clib_warning ("paws failed: 24-day old segment");
314 /* Drop after ack if not rst. Resets can fail paws check as per
315 * RFC 7323 sec. 5.2: When an <RST> segment is received, it MUST NOT
316 * be subjected to the PAWS check by verifying an acceptable value in
318 else if (!tcp_rst (th0))
320 tcp_program_ack (tc0);
321 TCP_EVT (TCP_EVT_DUPACK_SENT, tc0, vnet_buffer (b0)->tcp);
326 /* 1st: check sequence number */
327 if (!tcp_segment_in_rcv_wnd (tc0, vnet_buffer (b0)->tcp.seq_number,
328 vnet_buffer (b0)->tcp.seq_end))
330 /* SYN/SYN-ACK retransmit */
332 && vnet_buffer (b0)->tcp.seq_number == tc0->rcv_nxt - 1)
334 tcp_options_parse (th0, &tc0->rcv_opts, 1);
335 if (tc0->state == TCP_STATE_SYN_RCVD)
337 tcp_send_synack (tc0);
338 TCP_EVT (TCP_EVT_SYN_RCVD, tc0, 0);
339 *error0 = TCP_ERROR_SYNS_RCVD;
343 tcp_program_ack (tc0);
344 TCP_EVT (TCP_EVT_SYNACK_RCVD, tc0);
345 *error0 = TCP_ERROR_SYN_ACKS_RCVD;
350 /* If our window is 0 and the packet is in sequence, let it pass
351 * through for ack processing. It should be dropped later. */
352 if (tc0->rcv_wnd < tc0->snd_mss
353 && tc0->rcv_nxt == vnet_buffer (b0)->tcp.seq_number)
356 /* If we entered recovery and peer did so as well, there's a chance that
357 * dup acks won't be acceptable on either end because seq_end may be less
358 * than rcv_las. This can happen if acks are lost in both directions. */
359 if (tcp_in_recovery (tc0)
360 && seq_geq (vnet_buffer (b0)->tcp.seq_number,
361 tc0->rcv_las - tc0->rcv_wnd)
362 && seq_leq (vnet_buffer (b0)->tcp.seq_end,
363 tc0->rcv_nxt + tc0->rcv_wnd))
366 *error0 = TCP_ERROR_RCV_WND;
368 /* If we advertised a zero rcv_wnd and the segment is in the past or the
369 * next one that we expect, it is probably a window probe */
370 if ((tc0->flags & TCP_CONN_ZERO_RWND_SENT)
371 && seq_lt (vnet_buffer (b0)->tcp.seq_end,
372 tc0->rcv_las + tc0->rcv_opts.mss))
373 *error0 = TCP_ERROR_ZERO_RWND;
375 tc0->errors.below_data_wnd += seq_lt (vnet_buffer (b0)->tcp.seq_end,
378 /* If not RST, send dup ack */
381 tcp_program_dupack (tc0);
382 TCP_EVT (TCP_EVT_DUPACK_SENT, tc0, vnet_buffer (b0)->tcp);
390 /* 2nd: check the RST bit */
391 if (PREDICT_FALSE (tcp_rst (th0)))
393 tcp_connection_reset (tc0);
394 *error0 = TCP_ERROR_RST_RCVD;
398 /* 3rd: check security and precedence (skip) */
400 /* 4th: check the SYN bit (in window) */
401 if (PREDICT_FALSE (tcp_syn (th0)))
403 /* As per RFC5961 send challenge ack instead of reset */
404 tcp_program_ack (tc0);
405 *error0 = TCP_ERROR_SPURIOUS_SYN;
409 /* If segment in window, save timestamp */
410 tcp_update_timestamp (tc0, vnet_buffer (b0)->tcp.seq_number,
411 vnet_buffer (b0)->tcp.seq_end);
419 tcp_rcv_ack_no_cc (tcp_connection_t * tc, vlib_buffer_t * b, u32 * error)
421 /* SND.UNA =< SEG.ACK =< SND.NXT */
422 if (!(seq_leq (tc->snd_una, vnet_buffer (b)->tcp.ack_number)
423 && seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)))
425 if (seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_una_max)
426 && seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_una))
428 tc->snd_nxt = vnet_buffer (b)->tcp.ack_number;
431 *error = TCP_ERROR_ACK_INVALID;
436 tc->bytes_acked = vnet_buffer (b)->tcp.ack_number - tc->snd_una;
437 tc->snd_una = vnet_buffer (b)->tcp.ack_number;
438 *error = TCP_ERROR_ACK_OK;
443 * Compute smoothed RTT as per VJ's '88 SIGCOMM and RFC6298
445 * Note that although the original article, srtt and rttvar are scaled
446 * to minimize round-off errors, here we don't. Instead, we rely on
447 * better precision time measurements.
449 * TODO support us rtt resolution
452 tcp_estimate_rtt (tcp_connection_t * tc, u32 mrtt)
458 err = mrtt - tc->srtt;
460 /* XXX Drop in RTT results in RTTVAR increase and bigger RTO.
461 * The increase should be bound */
462 tc->srtt = clib_max ((int) tc->srtt + (err >> 3), 1);
463 diff = (clib_abs (err) - (int) tc->rttvar) >> 2;
464 tc->rttvar = clib_max ((int) tc->rttvar + diff, 1);
468 /* First measurement. */
470 tc->rttvar = mrtt >> 1;
474 #ifndef CLIB_MARCH_VARIANT
476 tcp_update_rto (tcp_connection_t * tc)
478 tc->rto = clib_min (tc->srtt + (tc->rttvar << 2), TCP_RTO_MAX);
479 tc->rto = clib_max (tc->rto, TCP_RTO_MIN);
481 #endif /* CLIB_MARCH_VARIANT */
484 * Update RTT estimate and RTO timer
486 * Measure RTT: We have two sources of RTT measurements: TSOPT and ACK
487 * timing. Middle boxes are known to fiddle with TCP options so we
488 * should give higher priority to ACK timing.
490 * This should be called only if previously sent bytes have been acked.
492 * return 1 if valid rtt 0 otherwise
495 tcp_update_rtt (tcp_connection_t * tc, u32 ack)
499 /* Karn's rule, part 1. Don't use retransmitted segments to estimate
500 * RTT because they're ambiguous. */
501 if (tcp_in_cong_recovery (tc) || tc->sack_sb.sacked_bytes)
503 if (tcp_in_recovery (tc))
508 if (tc->rtt_ts && seq_geq (ack, tc->rtt_seq))
510 f64 sample = tcp_time_now_us (tc->c_thread_index) - tc->rtt_ts;
511 tc->mrtt_us = tc->mrtt_us + (sample - tc->mrtt_us) * 0.125;
512 mrtt = clib_max ((u32) (sample * THZ), 1);
513 /* Allow measuring of a new RTT */
516 /* As per RFC7323 TSecr can be used for RTTM only if the segment advances
517 * snd_una, i.e., the left side of the send window:
518 * seq_lt (tc->snd_una, ack). This is a condition for calling update_rtt */
519 else if (tcp_opts_tstamp (&tc->rcv_opts) && tc->rcv_opts.tsecr)
521 u32 now = tcp_tstamp (tc);
522 mrtt = clib_max (now - tc->rcv_opts.tsecr, 1);
525 /* Ignore dubious measurements */
526 if (mrtt == 0 || mrtt > TCP_RTT_MAX)
529 tcp_estimate_rtt (tc, mrtt);
533 /* If we got here something must've been ACKed so make sure boff is 0,
534 * even if mrtt is not valid since we update the rto lower */
542 tcp_estimate_initial_rtt (tcp_connection_t * tc)
544 u8 thread_index = vlib_num_workers ()? 1 : 0;
549 tc->mrtt_us = tcp_time_now_us (thread_index) - tc->rtt_ts;
550 tc->mrtt_us = clib_max (tc->mrtt_us, 0.0001);
551 mrtt = clib_max ((u32) (tc->mrtt_us * THZ), 1);
556 mrtt = tcp_time_now_w_thread (thread_index) - tc->rcv_opts.tsecr;
557 mrtt = clib_max (mrtt, 1);
558 /* Due to retransmits we don't know the initial mrtt */
559 if (tc->rto_boff && mrtt > 1 * THZ)
561 tc->mrtt_us = (f64) mrtt *TCP_TICK;
564 if (mrtt > 0 && mrtt < TCP_RTT_MAX)
565 tcp_estimate_rtt (tc, mrtt);
570 * Dequeue bytes for connections that have received acks in last burst
573 tcp_handle_postponed_dequeues (tcp_worker_ctx_t * wrk)
575 u32 thread_index = wrk->vm->thread_index;
576 u32 *pending_deq_acked;
577 tcp_connection_t *tc;
580 if (!vec_len (wrk->pending_deq_acked))
583 pending_deq_acked = wrk->pending_deq_acked;
584 for (i = 0; i < vec_len (pending_deq_acked); i++)
586 tc = tcp_connection_get (pending_deq_acked[i], thread_index);
587 tc->flags &= ~TCP_CONN_DEQ_PENDING;
589 if (PREDICT_FALSE (!tc->burst_acked))
592 /* Dequeue the newly ACKed bytes */
593 session_tx_fifo_dequeue_drop (&tc->connection, tc->burst_acked);
595 tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una);
597 if (PREDICT_FALSE (tc->flags & TCP_CONN_PSH_PENDING))
599 if (seq_leq (tc->psh_seq, tc->snd_una))
600 tc->flags &= ~TCP_CONN_PSH_PENDING;
603 /* If everything has been acked, stop retransmit timer
604 * otherwise update. */
605 tcp_retransmit_timer_update (tc);
607 /* If not congested, update pacer based on our new
609 if (!tcp_in_fastrecovery (tc))
610 tcp_connection_tx_pacer_update (tc);
612 _vec_len (wrk->pending_deq_acked) = 0;
616 tcp_program_dequeue (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
618 if (!(tc->flags & TCP_CONN_DEQ_PENDING))
620 vec_add1 (wrk->pending_deq_acked, tc->c_c_index);
621 tc->flags |= TCP_CONN_DEQ_PENDING;
623 tc->burst_acked += tc->bytes_acked + tc->sack_sb.snd_una_adv;
627 * Check if duplicate ack as per RFC5681 Sec. 2
630 tcp_ack_is_dupack (tcp_connection_t * tc, vlib_buffer_t * b, u32 prev_snd_wnd,
633 return ((vnet_buffer (b)->tcp.ack_number == prev_snd_una)
634 && seq_gt (tc->snd_nxt, tc->snd_una)
635 && (vnet_buffer (b)->tcp.seq_end == vnet_buffer (b)->tcp.seq_number)
636 && (prev_snd_wnd == tc->snd_wnd));
640 * Checks if ack is a congestion control event.
643 tcp_ack_is_cc_event (tcp_connection_t * tc, vlib_buffer_t * b,
644 u32 prev_snd_wnd, u32 prev_snd_una, u8 * is_dack)
646 /* Check if ack is duplicate. Per RFC 6675, ACKs that SACK new data are
647 * defined to be 'duplicate' */
648 *is_dack = tc->sack_sb.last_sacked_bytes
649 || tcp_ack_is_dupack (tc, b, prev_snd_wnd, prev_snd_una);
651 return ((*is_dack || tcp_in_cong_recovery (tc)) && !tcp_is_lost_fin (tc));
654 #ifndef CLIB_MARCH_VARIANT
656 scoreboard_hole_index (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole)
658 ASSERT (!pool_is_free_index (sb->holes, hole - sb->holes));
659 return hole - sb->holes;
663 scoreboard_hole_bytes (sack_scoreboard_hole_t * hole)
665 return hole->end - hole->start;
668 sack_scoreboard_hole_t *
669 scoreboard_get_hole (sack_scoreboard_t * sb, u32 index)
671 if (index != TCP_INVALID_SACK_HOLE_INDEX)
672 return pool_elt_at_index (sb->holes, index);
676 sack_scoreboard_hole_t *
677 scoreboard_next_hole (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole)
679 if (hole->next != TCP_INVALID_SACK_HOLE_INDEX)
680 return pool_elt_at_index (sb->holes, hole->next);
684 sack_scoreboard_hole_t *
685 scoreboard_prev_hole (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole)
687 if (hole->prev != TCP_INVALID_SACK_HOLE_INDEX)
688 return pool_elt_at_index (sb->holes, hole->prev);
692 sack_scoreboard_hole_t *
693 scoreboard_first_hole (sack_scoreboard_t * sb)
695 if (sb->head != TCP_INVALID_SACK_HOLE_INDEX)
696 return pool_elt_at_index (sb->holes, sb->head);
700 sack_scoreboard_hole_t *
701 scoreboard_last_hole (sack_scoreboard_t * sb)
703 if (sb->tail != TCP_INVALID_SACK_HOLE_INDEX)
704 return pool_elt_at_index (sb->holes, sb->tail);
709 scoreboard_remove_hole (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole)
711 sack_scoreboard_hole_t *next, *prev;
713 if (hole->next != TCP_INVALID_SACK_HOLE_INDEX)
715 next = pool_elt_at_index (sb->holes, hole->next);
716 next->prev = hole->prev;
720 sb->tail = hole->prev;
723 if (hole->prev != TCP_INVALID_SACK_HOLE_INDEX)
725 prev = pool_elt_at_index (sb->holes, hole->prev);
726 prev->next = hole->next;
730 sb->head = hole->next;
733 if (scoreboard_hole_index (sb, hole) == sb->cur_rxt_hole)
734 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
736 /* Poison the entry */
738 clib_memset (hole, 0xfe, sizeof (*hole));
740 pool_put (sb->holes, hole);
743 static sack_scoreboard_hole_t *
744 scoreboard_insert_hole (sack_scoreboard_t * sb, u32 prev_index,
747 sack_scoreboard_hole_t *hole, *next, *prev;
750 pool_get (sb->holes, hole);
751 clib_memset (hole, 0, sizeof (*hole));
755 hole_index = scoreboard_hole_index (sb, hole);
757 prev = scoreboard_get_hole (sb, prev_index);
760 hole->prev = prev_index;
761 hole->next = prev->next;
763 if ((next = scoreboard_next_hole (sb, hole)))
764 next->prev = hole_index;
766 sb->tail = hole_index;
768 prev->next = hole_index;
772 sb->head = hole_index;
773 hole->prev = TCP_INVALID_SACK_HOLE_INDEX;
774 hole->next = TCP_INVALID_SACK_HOLE_INDEX;
779 #endif /* CLIB_MARCH_VARIANT */
781 #ifndef CLIB_MARCH_VARIANT
783 scoreboard_update_bytes (tcp_connection_t * tc, sack_scoreboard_t * sb)
785 sack_scoreboard_hole_t *left, *right;
786 u32 bytes = 0, blks = 0;
788 sb->last_lost_bytes = 0;
790 sb->sacked_bytes = 0;
791 left = scoreboard_last_hole (sb);
795 if (seq_gt (sb->high_sacked, left->end))
797 bytes = sb->high_sacked - left->end;
801 while ((right = left)
802 && bytes < (TCP_DUPACK_THRESHOLD - 1) * tc->snd_mss
803 && blks < TCP_DUPACK_THRESHOLD
804 /* left not updated if above conditions fail */
805 && (left = scoreboard_prev_hole (sb, right)))
807 bytes += right->start - left->end;
811 /* left is first lost */
816 sb->lost_bytes += scoreboard_hole_bytes (right);
817 sb->last_lost_bytes += left->is_lost ? 0 : left->end - left->start;
819 left = scoreboard_prev_hole (sb, right);
821 bytes += right->start - left->end;
823 while ((right = left));
826 sb->sacked_bytes = bytes;
830 * Figure out the next hole to retransmit
832 * Follows logic proposed in RFC6675 Sec. 4, NextSeg()
834 sack_scoreboard_hole_t *
835 scoreboard_next_rxt_hole (sack_scoreboard_t * sb,
836 sack_scoreboard_hole_t * start,
837 u8 have_unsent, u8 * can_rescue, u8 * snd_limited)
839 sack_scoreboard_hole_t *hole = 0;
841 hole = start ? start : scoreboard_first_hole (sb);
842 while (hole && seq_leq (hole->end, sb->high_rxt) && hole->is_lost)
843 hole = scoreboard_next_hole (sb, hole);
845 /* Nothing, return */
848 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
852 /* Rule (1): if higher than rxt, less than high_sacked and lost */
853 if (hole->is_lost && seq_lt (hole->start, sb->high_sacked))
855 sb->cur_rxt_hole = scoreboard_hole_index (sb, hole);
859 /* Rule (2): available unsent data */
862 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
865 /* Rule (3): if hole not lost */
866 else if (seq_lt (hole->start, sb->high_sacked))
869 sb->cur_rxt_hole = scoreboard_hole_index (sb, hole);
871 /* Rule (4): if hole beyond high_sacked */
874 ASSERT (seq_geq (hole->start, sb->high_sacked));
877 /* HighRxt MUST NOT be updated */
882 if (hole && seq_lt (sb->high_rxt, hole->start))
883 sb->high_rxt = hole->start;
887 #endif /* CLIB_MARCH_VARIANT */
890 scoreboard_init_high_rxt (sack_scoreboard_t * sb, u32 snd_una)
892 sack_scoreboard_hole_t *hole;
893 hole = scoreboard_first_hole (sb);
896 snd_una = seq_gt (snd_una, hole->start) ? snd_una : hole->start;
897 sb->cur_rxt_hole = sb->head;
899 sb->high_rxt = snd_una;
900 sb->rescue_rxt = snd_una - 1;
903 #ifndef CLIB_MARCH_VARIANT
905 scoreboard_init (sack_scoreboard_t * sb)
907 sb->head = TCP_INVALID_SACK_HOLE_INDEX;
908 sb->tail = TCP_INVALID_SACK_HOLE_INDEX;
909 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
913 scoreboard_clear (sack_scoreboard_t * sb)
915 sack_scoreboard_hole_t *hole;
916 while ((hole = scoreboard_first_hole (sb)))
918 scoreboard_remove_hole (sb, hole);
920 ASSERT (sb->head == sb->tail && sb->head == TCP_INVALID_SACK_HOLE_INDEX);
921 ASSERT (pool_elts (sb->holes) == 0);
922 sb->sacked_bytes = 0;
923 sb->last_sacked_bytes = 0;
924 sb->last_bytes_delivered = 0;
929 sb->last_lost_bytes = 0;
930 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
932 #endif /* CLIB_MARCH_VARIANT */
935 * Test that scoreboard is sane after recovery
937 * Returns 1 if scoreboard is empty or if first hole beyond
941 tcp_scoreboard_is_sane_post_recovery (tcp_connection_t * tc)
943 sack_scoreboard_hole_t *hole;
944 hole = scoreboard_first_hole (&tc->sack_sb);
945 return (!hole || (seq_geq (hole->start, tc->snd_una)
946 && seq_lt (hole->end, tc->snd_nxt)));
949 #ifndef CLIB_MARCH_VARIANT
952 tcp_rcv_sacks (tcp_connection_t * tc, u32 ack)
954 sack_scoreboard_hole_t *hole, *next_hole, *last_hole;
955 u32 blk_index = 0, old_sacked_bytes, hole_index;
956 sack_scoreboard_t *sb = &tc->sack_sb;
957 sack_block_t *blk, tmp;
960 sb->last_sacked_bytes = 0;
961 sb->last_bytes_delivered = 0;
964 if (!tcp_opts_sack (&tc->rcv_opts)
965 && sb->head == TCP_INVALID_SACK_HOLE_INDEX)
968 old_sacked_bytes = sb->sacked_bytes;
970 /* Remove invalid blocks */
971 blk = tc->rcv_opts.sacks;
972 while (blk < vec_end (tc->rcv_opts.sacks))
974 if (seq_lt (blk->start, blk->end)
975 && seq_gt (blk->start, tc->snd_una)
976 && seq_gt (blk->start, ack)
977 && seq_lt (blk->start, tc->snd_nxt)
978 && seq_leq (blk->end, tc->snd_nxt))
983 vec_del1 (tc->rcv_opts.sacks, blk - tc->rcv_opts.sacks);
986 /* Add block for cumulative ack */
987 if (seq_gt (ack, tc->snd_una))
989 tmp.start = tc->snd_una;
991 vec_add1 (tc->rcv_opts.sacks, tmp);
994 if (vec_len (tc->rcv_opts.sacks) == 0)
997 tcp_scoreboard_trace_add (tc, ack);
999 /* Make sure blocks are ordered */
1000 for (i = 0; i < vec_len (tc->rcv_opts.sacks); i++)
1001 for (j = i + 1; j < vec_len (tc->rcv_opts.sacks); j++)
1002 if (seq_lt (tc->rcv_opts.sacks[j].start, tc->rcv_opts.sacks[i].start))
1004 tmp = tc->rcv_opts.sacks[i];
1005 tc->rcv_opts.sacks[i] = tc->rcv_opts.sacks[j];
1006 tc->rcv_opts.sacks[j] = tmp;
1009 if (sb->head == TCP_INVALID_SACK_HOLE_INDEX)
1011 /* If no holes, insert the first that covers all outstanding bytes */
1012 last_hole = scoreboard_insert_hole (sb, TCP_INVALID_SACK_HOLE_INDEX,
1013 tc->snd_una, tc->snd_nxt);
1014 sb->tail = scoreboard_hole_index (sb, last_hole);
1015 tmp = tc->rcv_opts.sacks[vec_len (tc->rcv_opts.sacks) - 1];
1016 sb->high_sacked = tmp.end;
1020 /* If we have holes but snd_una_max is beyond the last hole, update
1022 tmp = tc->rcv_opts.sacks[vec_len (tc->rcv_opts.sacks) - 1];
1023 last_hole = scoreboard_last_hole (sb);
1024 if (seq_gt (tc->snd_nxt, last_hole->end))
1026 if (seq_geq (last_hole->start, sb->high_sacked))
1028 last_hole->end = tc->snd_nxt;
1030 /* New hole after high sacked block */
1031 else if (seq_lt (sb->high_sacked, tc->snd_nxt))
1033 scoreboard_insert_hole (sb, sb->tail, sb->high_sacked,
1037 /* Keep track of max byte sacked for when the last hole
1039 if (seq_gt (tmp.end, sb->high_sacked))
1040 sb->high_sacked = tmp.end;
1043 /* Walk the holes with the SACK blocks */
1044 hole = pool_elt_at_index (sb->holes, sb->head);
1045 while (hole && blk_index < vec_len (tc->rcv_opts.sacks))
1047 blk = &tc->rcv_opts.sacks[blk_index];
1048 if (seq_leq (blk->start, hole->start))
1050 /* Block covers hole. Remove hole */
1051 if (seq_geq (blk->end, hole->end))
1053 next_hole = scoreboard_next_hole (sb, hole);
1055 /* Byte accounting: snd_una needs to be advanced */
1056 if (blk->end == ack)
1060 if (seq_lt (ack, next_hole->start))
1061 sb->snd_una_adv = next_hole->start - ack;
1062 sb->last_bytes_delivered +=
1063 next_hole->start - hole->end;
1067 ASSERT (seq_geq (sb->high_sacked, ack));
1068 sb->snd_una_adv = sb->high_sacked - ack;
1069 sb->last_bytes_delivered += sb->high_sacked - hole->end;
1072 scoreboard_remove_hole (sb, hole);
1075 /* Partial 'head' overlap */
1078 if (seq_gt (blk->end, hole->start))
1080 hole->start = blk->end;
1087 /* Hole must be split */
1088 if (seq_lt (blk->end, hole->end))
1090 hole_index = scoreboard_hole_index (sb, hole);
1091 next_hole = scoreboard_insert_hole (sb, hole_index, blk->end,
1094 /* Pool might've moved */
1095 hole = scoreboard_get_hole (sb, hole_index);
1096 hole->end = blk->start;
1098 ASSERT (hole->next == scoreboard_hole_index (sb, next_hole));
1100 else if (seq_lt (blk->start, hole->end))
1102 hole->end = blk->start;
1104 hole = scoreboard_next_hole (sb, hole);
1108 if (pool_elts (sb->holes) == 1)
1110 hole = scoreboard_first_hole (sb);
1111 if (hole->start == ack + sb->snd_una_adv && hole->end == tc->snd_nxt)
1112 scoreboard_remove_hole (sb, hole);
1115 scoreboard_update_bytes (tc, sb);
1116 sb->last_sacked_bytes = sb->sacked_bytes
1117 - (old_sacked_bytes - sb->last_bytes_delivered);
1119 ASSERT (sb->last_sacked_bytes <= sb->sacked_bytes || tcp_in_recovery (tc));
1120 ASSERT (sb->sacked_bytes == 0 || tcp_in_recovery (tc)
1121 || sb->sacked_bytes < tc->snd_nxt - seq_max (tc->snd_una, ack));
1122 ASSERT (sb->last_sacked_bytes + sb->lost_bytes <= tc->snd_nxt
1123 - seq_max (tc->snd_una, ack) || tcp_in_recovery (tc));
1124 ASSERT (sb->head == TCP_INVALID_SACK_HOLE_INDEX || tcp_in_recovery (tc)
1125 || sb->holes[sb->head].start == ack + sb->snd_una_adv);
1126 ASSERT (sb->last_lost_bytes <= sb->lost_bytes);
1128 TCP_EVT (TCP_EVT_CC_SCOREBOARD, tc);
1130 #endif /* CLIB_MARCH_VARIANT */
1133 * Try to update snd_wnd based on feedback received from peer.
1135 * If successful, and new window is 'effectively' 0, activate persist
1139 tcp_update_snd_wnd (tcp_connection_t * tc, u32 seq, u32 ack, u32 snd_wnd)
1141 /* If (SND.WL1 < SEG.SEQ or (SND.WL1 = SEG.SEQ and SND.WL2 =< SEG.ACK)), set
1142 * SND.WND <- SEG.WND, set SND.WL1 <- SEG.SEQ, and set SND.WL2 <- SEG.ACK */
1143 if (seq_lt (tc->snd_wl1, seq)
1144 || (tc->snd_wl1 == seq && seq_leq (tc->snd_wl2, ack)))
1146 tc->snd_wnd = snd_wnd;
1149 TCP_EVT (TCP_EVT_SND_WND, tc);
1151 if (PREDICT_FALSE (tc->snd_wnd < tc->snd_mss))
1153 /* Set persist timer if not set and we just got 0 wnd */
1154 if (!tcp_timer_is_active (tc, TCP_TIMER_PERSIST)
1155 && !tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT))
1156 tcp_persist_timer_set (tc);
1160 tcp_persist_timer_reset (tc);
1161 if (PREDICT_FALSE (!tcp_in_recovery (tc) && tc->rto_boff > 0))
1164 tcp_update_rto (tc);
1170 #ifndef CLIB_MARCH_VARIANT
1172 * Init loss recovery/fast recovery.
1174 * Triggered by dup acks as opposed to timer timeout. Note that cwnd is
1175 * updated in @ref tcp_cc_handle_event after fast retransmit
1178 tcp_cc_init_congestion (tcp_connection_t * tc)
1180 tcp_fastrecovery_on (tc);
1181 tc->snd_congestion = tc->snd_nxt;
1182 tc->cwnd_acc_bytes = 0;
1183 tc->snd_rxt_bytes = 0;
1184 tc->prev_ssthresh = tc->ssthresh;
1185 tc->prev_cwnd = tc->cwnd;
1186 tc->cc_algo->congestion (tc);
1187 tc->fr_occurences += 1;
1188 TCP_EVT (TCP_EVT_CC_EVT, tc, 4);
1190 #endif /* CLIB_MARCH_VARIANT */
1193 tcp_cc_recovery_exit (tcp_connection_t * tc)
1196 tcp_update_rto (tc);
1199 tcp_recovery_off (tc);
1200 TCP_EVT (TCP_EVT_CC_EVT, tc, 3);
1203 #ifndef CLIB_MARCH_VARIANT
1205 tcp_cc_fastrecovery_clear (tcp_connection_t * tc)
1207 tc->snd_rxt_bytes = 0;
1208 tc->rcv_dupacks = 0;
1211 tcp_fastrecovery_off (tc);
1212 tcp_fastrecovery_first_off (tc);
1213 tc->flags &= ~TCP_CONN_FRXT_PENDING;
1215 TCP_EVT (TCP_EVT_CC_EVT, tc, 3);
1217 #endif /* CLIB_MARCH_VARIANT */
1220 tcp_cc_congestion_undo (tcp_connection_t * tc)
1222 tc->cwnd = tc->prev_cwnd;
1223 tc->ssthresh = tc->prev_ssthresh;
1224 tc->rcv_dupacks = 0;
1225 if (tcp_in_recovery (tc))
1227 tcp_cc_recovery_exit (tc);
1228 tc->snd_nxt = seq_max (tc->snd_nxt, tc->snd_congestion);
1230 else if (tcp_in_fastrecovery (tc))
1232 tcp_cc_fastrecovery_clear (tc);
1234 tcp_cc_undo_recovery (tc);
1235 ASSERT (tc->rto_boff == 0);
1236 TCP_EVT (TCP_EVT_CC_EVT, tc, 5);
1240 tcp_cc_is_spurious_timeout_rxt (tcp_connection_t * tc)
1242 return (tcp_in_recovery (tc) && tc->rto_boff == 1
1244 && tcp_opts_tstamp (&tc->rcv_opts)
1245 && timestamp_lt (tc->rcv_opts.tsecr, tc->snd_rxt_ts));
1249 tcp_cc_is_spurious_fast_rxt (tcp_connection_t * tc)
1251 return (tcp_in_fastrecovery (tc)
1252 && tc->cwnd > tc->ssthresh + 3 * tc->snd_mss);
1256 tcp_cc_is_spurious_retransmit (tcp_connection_t * tc)
1258 return (tcp_cc_is_spurious_timeout_rxt (tc)
1259 || tcp_cc_is_spurious_fast_rxt (tc));
1263 tcp_cc_recover (tcp_connection_t * tc)
1265 ASSERT (tcp_in_cong_recovery (tc));
1266 if (tcp_cc_is_spurious_retransmit (tc))
1268 tcp_cc_congestion_undo (tc);
1272 if (tcp_in_recovery (tc))
1273 tcp_cc_recovery_exit (tc);
1274 else if (tcp_in_fastrecovery (tc))
1276 tcp_cc_recovered (tc);
1277 tcp_cc_fastrecovery_clear (tc);
1280 ASSERT (tc->rto_boff == 0);
1281 ASSERT (!tcp_in_cong_recovery (tc));
1282 ASSERT (tcp_scoreboard_is_sane_post_recovery (tc));
1287 tcp_cc_update (tcp_connection_t * tc, tcp_rate_sample_t * rs)
1289 ASSERT (!tcp_in_cong_recovery (tc) || tcp_is_lost_fin (tc));
1291 /* Congestion avoidance */
1292 tcp_cc_rcv_ack (tc, rs);
1294 /* If a cumulative ack, make sure dupacks is 0 */
1295 tc->rcv_dupacks = 0;
1297 /* When dupacks hits the threshold we only enter fast retransmit if
1298 * cumulative ack covers more than snd_congestion. Should snd_una
1299 * wrap this test may fail under otherwise valid circumstances.
1300 * Therefore, proactively update snd_congestion when wrap detected. */
1302 (seq_leq (tc->snd_congestion, tc->snd_una - tc->bytes_acked)
1303 && seq_gt (tc->snd_congestion, tc->snd_una)))
1304 tc->snd_congestion = tc->snd_una - 1;
1308 tcp_should_fastrecover_sack (tcp_connection_t * tc)
1310 return (TCP_DUPACK_THRESHOLD - 1) * tc->snd_mss < tc->sack_sb.sacked_bytes;
1314 tcp_should_fastrecover (tcp_connection_t * tc)
1316 return (tc->rcv_dupacks == TCP_DUPACK_THRESHOLD
1317 || tcp_should_fastrecover_sack (tc));
1321 * One function to rule them all ... and in the darkness bind them
1324 tcp_cc_handle_event (tcp_connection_t * tc, tcp_rate_sample_t * rs,
1329 if (tcp_in_fastrecovery (tc) && tcp_opts_sack_permitted (&tc->rcv_opts))
1331 if (tc->bytes_acked)
1333 tcp_program_fastretransmit (tc);
1337 * Duplicate ACK. Check if we should enter fast recovery, or if already in
1338 * it account for the bytes that left the network.
1340 else if (is_dack && !tcp_in_recovery (tc))
1342 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
1343 ASSERT (tc->snd_una != tc->snd_nxt || tc->sack_sb.last_sacked_bytes);
1347 /* Pure duplicate ack. If some data got acked, it's handled lower */
1348 if (tc->rcv_dupacks > TCP_DUPACK_THRESHOLD && !tc->bytes_acked)
1350 ASSERT (tcp_in_fastrecovery (tc));
1351 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
1354 else if (tcp_should_fastrecover (tc))
1358 ASSERT (!tcp_in_fastrecovery (tc));
1360 /* Heuristic to catch potential late dupacks
1361 * after fast retransmit exits */
1362 if (is_dack && tc->snd_una == tc->snd_congestion
1363 && timestamp_leq (tc->rcv_opts.tsecr, tc->tsecr_last_ack))
1365 tc->rcv_dupacks = 0;
1369 tcp_cc_init_congestion (tc);
1371 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1372 scoreboard_init_high_rxt (&tc->sack_sb, tc->snd_una);
1374 /* Constrain rate until we get a partial ack */
1375 pacer_wnd = clib_max (0.1 * tc->cwnd, 2 * tc->snd_mss);
1376 tcp_connection_tx_pacer_reset (tc, pacer_wnd,
1377 0 /* start bucket */ );
1378 tcp_program_fastretransmit (tc);
1381 else if (!tc->bytes_acked
1382 || (tc->bytes_acked && !tcp_in_cong_recovery (tc)))
1384 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
1390 /* Don't allow entry in fast recovery if still in recovery, for now */
1391 else if (0 && is_dack && tcp_in_recovery (tc))
1393 /* If of of the two conditions lower hold, reset dupacks because
1394 * we're probably after timeout (RFC6582 heuristics).
1395 * If Cumulative ack does not cover more than congestion threshold,
1397 * 1) The following doesn't hold: The congestion window is greater
1398 * than SMSS bytes and the difference between highest_ack
1399 * and prev_highest_ack is at most 4*SMSS bytes
1400 * 2) Echoed timestamp in the last non-dup ack does not equal the
1403 if (seq_leq (tc->snd_una, tc->snd_congestion)
1404 && ((!(tc->cwnd > tc->snd_mss
1405 && tc->bytes_acked <= 4 * tc->snd_mss))
1406 || (tc->rcv_opts.tsecr != tc->tsecr_last_ack)))
1408 tc->rcv_dupacks = 0;
1413 if (!tc->bytes_acked)
1417 TCP_EVT (TCP_EVT_CC_PACK, tc);
1420 * Legitimate ACK. 1) See if we can exit recovery
1423 /* Update the pacing rate. For the first partial ack we move from
1424 * the artificially constrained rate to the one after congestion */
1425 tcp_connection_tx_pacer_update (tc);
1427 if (seq_geq (tc->snd_una, tc->snd_congestion))
1429 tcp_retransmit_timer_update (tc);
1431 /* If spurious return, we've already updated everything */
1432 if (tcp_cc_recover (tc))
1434 tc->tsecr_last_ack = tc->rcv_opts.tsecr;
1438 /* Treat as congestion avoidance ack */
1439 tcp_cc_rcv_ack (tc, rs);
1444 * Legitimate ACK. 2) If PARTIAL ACK try to retransmit
1447 /* XXX limit this only to first partial ack? */
1448 tcp_retransmit_timer_update (tc);
1450 /* RFC6675: If the incoming ACK is a cumulative acknowledgment,
1451 * reset dupacks to 0. Also needed if in congestion recovery */
1452 tc->rcv_dupacks = 0;
1454 /* Post RTO timeout don't try anything fancy */
1455 if (tcp_in_recovery (tc))
1457 tcp_cc_rcv_ack (tc, rs);
1458 transport_add_tx_event (&tc->connection);
1462 /* Remove retransmitted bytes that have been delivered */
1463 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1465 ASSERT (tc->bytes_acked + tc->sack_sb.snd_una_adv
1466 >= tc->sack_sb.last_bytes_delivered
1467 || (tc->flags & TCP_CONN_FINSNT));
1469 /* If we have sacks and we haven't gotten an ack beyond high_rxt,
1470 * remove sacked bytes delivered */
1471 if (seq_lt (tc->snd_una, tc->sack_sb.high_rxt))
1473 rxt_delivered = tc->bytes_acked + tc->sack_sb.snd_una_adv
1474 - tc->sack_sb.last_bytes_delivered;
1475 ASSERT (tc->snd_rxt_bytes >= rxt_delivered);
1476 tc->snd_rxt_bytes -= rxt_delivered;
1480 /* Apparently all retransmitted holes have been acked */
1481 tc->snd_rxt_bytes = 0;
1482 tc->sack_sb.high_rxt = tc->snd_una;
1487 tcp_fastrecovery_first_on (tc);
1488 if (tc->snd_rxt_bytes > tc->bytes_acked)
1489 tc->snd_rxt_bytes -= tc->bytes_acked;
1491 tc->snd_rxt_bytes = 0;
1494 tcp_cc_rcv_cong_ack (tc, TCP_CC_PARTIALACK, rs);
1497 * Since this was a partial ack, try to retransmit some more data
1499 tcp_program_fastretransmit (tc);
1503 * Process incoming ACK
1506 tcp_rcv_ack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
1507 tcp_header_t * th, u32 * error)
1509 u32 prev_snd_wnd, prev_snd_una;
1510 tcp_rate_sample_t rs = { 0 };
1513 TCP_EVT (TCP_EVT_CC_STAT, tc);
1515 /* If the ACK acks something not yet sent (SEG.ACK > SND.NXT) */
1516 if (PREDICT_FALSE (seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)))
1518 /* We've probably entered recovery and the peer still has some
1519 * of the data we've sent. Update snd_nxt and accept the ack */
1520 if (seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_una_max)
1521 && seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_una))
1523 tc->snd_nxt = vnet_buffer (b)->tcp.ack_number;
1527 tc->errors.above_ack_wnd += 1;
1528 *error = TCP_ERROR_ACK_FUTURE;
1529 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 0, vnet_buffer (b)->tcp.ack_number);
1533 /* If old ACK, probably it's an old dupack */
1534 if (PREDICT_FALSE (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una)))
1536 tc->errors.below_ack_wnd += 1;
1537 *error = TCP_ERROR_ACK_OLD;
1538 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 1, vnet_buffer (b)->tcp.ack_number);
1539 if (tcp_in_fastrecovery (tc) && tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
1540 tcp_cc_handle_event (tc, 0, 1);
1541 /* Don't drop yet */
1548 * Looks okay, process feedback
1551 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1552 tcp_rcv_sacks (tc, vnet_buffer (b)->tcp.ack_number);
1554 prev_snd_wnd = tc->snd_wnd;
1555 prev_snd_una = tc->snd_una;
1556 tcp_update_snd_wnd (tc, vnet_buffer (b)->tcp.seq_number,
1557 vnet_buffer (b)->tcp.ack_number,
1558 clib_net_to_host_u16 (th->window) << tc->snd_wscale);
1559 tc->bytes_acked = vnet_buffer (b)->tcp.ack_number - tc->snd_una;
1560 tc->snd_una = vnet_buffer (b)->tcp.ack_number + tc->sack_sb.snd_una_adv;
1561 tcp_validate_txf_size (tc, tc->bytes_acked);
1563 if (tc->bytes_acked)
1565 tcp_program_dequeue (wrk, tc);
1566 tcp_update_rtt (tc, vnet_buffer (b)->tcp.ack_number);
1569 if (tc->flags & TCP_CONN_RATE_SAMPLE)
1570 tcp_bt_sample_delivery_rate (tc, &rs);
1572 TCP_EVT (TCP_EVT_ACK_RCVD, tc);
1575 * Check if we have congestion event
1578 if (tcp_ack_is_cc_event (tc, b, prev_snd_wnd, prev_snd_una, &is_dack))
1580 tcp_cc_handle_event (tc, &rs, is_dack);
1581 tc->dupacks_in += is_dack;
1582 if (!tcp_in_cong_recovery (tc))
1584 *error = TCP_ERROR_ACK_OK;
1587 *error = TCP_ERROR_ACK_DUP;
1588 if (vnet_buffer (b)->tcp.data_len || tcp_is_fin (th))
1594 * Update congestion control (slow start/congestion avoidance)
1596 tcp_cc_update (tc, &rs);
1597 *error = TCP_ERROR_ACK_OK;
1602 tcp_program_disconnect (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
1604 if (!tcp_disconnect_pending (tc))
1606 vec_add1 (wrk->pending_disconnects, tc->c_c_index);
1607 tcp_disconnect_pending_on (tc);
1612 tcp_handle_disconnects (tcp_worker_ctx_t * wrk)
1614 u32 thread_index, *pending_disconnects;
1615 tcp_connection_t *tc;
1618 if (!vec_len (wrk->pending_disconnects))
1621 thread_index = wrk->vm->thread_index;
1622 pending_disconnects = wrk->pending_disconnects;
1623 for (i = 0; i < vec_len (pending_disconnects); i++)
1625 tc = tcp_connection_get (pending_disconnects[i], thread_index);
1626 tcp_disconnect_pending_off (tc);
1627 session_transport_closing_notify (&tc->connection);
1629 _vec_len (wrk->pending_disconnects) = 0;
1633 tcp_rcv_fin (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
1636 /* Reject out-of-order fins */
1637 if (vnet_buffer (b)->tcp.seq_end != tc->rcv_nxt)
1640 /* Account for the FIN and send ack */
1642 tcp_program_ack (tc);
1643 /* Enter CLOSE-WAIT and notify session. To avoid lingering
1644 * in CLOSE-WAIT, set timer (reuse WAITCLOSE). */
1645 tcp_connection_set_state (tc, TCP_STATE_CLOSE_WAIT);
1646 tcp_program_disconnect (wrk, tc);
1647 tcp_timer_update (tc, TCP_TIMER_WAITCLOSE, tcp_cfg.closewait_time);
1648 TCP_EVT (TCP_EVT_FIN_RCVD, tc);
1649 *error = TCP_ERROR_FIN_RCVD;
1652 #ifndef CLIB_MARCH_VARIANT
1654 tcp_sack_vector_is_sane (sack_block_t * sacks)
1657 for (i = 1; i < vec_len (sacks); i++)
1659 if (sacks[i - 1].end == sacks[i].start)
1666 * Build SACK list as per RFC2018.
1668 * Makes sure the first block contains the segment that generated the current
1669 * ACK and the following ones are the ones most recently reported in SACK
1672 * @param tc TCP connection for which the SACK list is updated
1673 * @param start Start sequence number of the newest SACK block
1674 * @param end End sequence of the newest SACK block
1677 tcp_update_sack_list (tcp_connection_t * tc, u32 start, u32 end)
1679 sack_block_t *new_list = tc->snd_sacks_fl, *block = 0;
1682 /* If the first segment is ooo add it to the list. Last write might've moved
1683 * rcv_nxt over the first segment. */
1684 if (seq_lt (tc->rcv_nxt, start))
1686 vec_add2 (new_list, block, 1);
1687 block->start = start;
1691 /* Find the blocks still worth keeping. */
1692 for (i = 0; i < vec_len (tc->snd_sacks); i++)
1694 /* Discard if rcv_nxt advanced beyond current block */
1695 if (seq_leq (tc->snd_sacks[i].start, tc->rcv_nxt))
1698 /* Merge or drop if segment overlapped by the new segment */
1699 if (block && (seq_geq (tc->snd_sacks[i].end, new_list[0].start)
1700 && seq_leq (tc->snd_sacks[i].start, new_list[0].end)))
1702 if (seq_lt (tc->snd_sacks[i].start, new_list[0].start))
1703 new_list[0].start = tc->snd_sacks[i].start;
1704 if (seq_lt (new_list[0].end, tc->snd_sacks[i].end))
1705 new_list[0].end = tc->snd_sacks[i].end;
1709 /* Save to new SACK list if we have space. */
1710 if (vec_len (new_list) < TCP_MAX_SACK_BLOCKS)
1711 vec_add1 (new_list, tc->snd_sacks[i]);
1714 ASSERT (vec_len (new_list) <= TCP_MAX_SACK_BLOCKS);
1716 /* Replace old vector with new one */
1717 vec_reset_length (tc->snd_sacks);
1718 tc->snd_sacks_fl = tc->snd_sacks;
1719 tc->snd_sacks = new_list;
1721 /* Segments should not 'touch' */
1722 ASSERT (tcp_sack_vector_is_sane (tc->snd_sacks));
1726 tcp_sack_list_bytes (tcp_connection_t * tc)
1729 for (i = 0; i < vec_len (tc->snd_sacks); i++)
1730 bytes += tc->snd_sacks[i].end - tc->snd_sacks[i].start;
1733 #endif /* CLIB_MARCH_VARIANT */
1735 /** Enqueue data for delivery to application */
1737 tcp_session_enqueue_data (tcp_connection_t * tc, vlib_buffer_t * b,
1740 int written, error = TCP_ERROR_ENQUEUED;
1742 ASSERT (seq_geq (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1744 written = session_enqueue_stream_connection (&tc->connection, b, 0,
1745 1 /* queue event */ , 1);
1746 tc->bytes_in += written;
1748 TCP_EVT (TCP_EVT_INPUT, tc, 0, data_len, written);
1750 /* Update rcv_nxt */
1751 if (PREDICT_TRUE (written == data_len))
1753 tc->rcv_nxt += written;
1755 /* If more data written than expected, account for out-of-order bytes. */
1756 else if (written > data_len)
1758 tc->rcv_nxt += written;
1759 TCP_EVT (TCP_EVT_CC_INPUT, tc, data_len, written);
1761 else if (written > 0)
1763 /* We've written something but FIFO is probably full now */
1764 tc->rcv_nxt += written;
1765 error = TCP_ERROR_PARTIALLY_ENQUEUED;
1769 return TCP_ERROR_FIFO_FULL;
1772 /* Update SACK list if need be */
1773 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1775 /* Remove SACK blocks that have been delivered */
1776 tcp_update_sack_list (tc, tc->rcv_nxt, tc->rcv_nxt);
1782 /** Enqueue out-of-order data */
1784 tcp_session_enqueue_ooo (tcp_connection_t * tc, vlib_buffer_t * b,
1790 ASSERT (seq_gt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1793 /* Enqueue out-of-order data with relative offset */
1794 rv = session_enqueue_stream_connection (&tc->connection, b,
1795 vnet_buffer (b)->tcp.seq_number -
1796 tc->rcv_nxt, 0 /* queue event */ ,
1799 /* Nothing written */
1802 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, 0);
1803 return TCP_ERROR_FIFO_FULL;
1806 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, data_len);
1807 tc->bytes_in += data_len;
1809 /* Update SACK list if in use */
1810 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1812 ooo_segment_t *newest;
1815 s0 = session_get (tc->c_s_index, tc->c_thread_index);
1817 /* Get the newest segment from the fifo */
1818 newest = svm_fifo_newest_ooo_segment (s0->rx_fifo);
1821 offset = ooo_segment_offset_prod (s0->rx_fifo, newest);
1822 ASSERT (offset <= vnet_buffer (b)->tcp.seq_number - tc->rcv_nxt);
1823 start = tc->rcv_nxt + offset;
1824 end = start + ooo_segment_length (s0->rx_fifo, newest);
1825 tcp_update_sack_list (tc, start, end);
1826 svm_fifo_newest_ooo_segment_reset (s0->rx_fifo);
1827 TCP_EVT (TCP_EVT_CC_SACKS, tc);
1831 return TCP_ERROR_ENQUEUED_OOO;
1835 * Check if ACK could be delayed. If ack can be delayed, it should return
1836 * true for a full frame. If we're always acking return 0.
1839 tcp_can_delack (tcp_connection_t * tc)
1841 /* Send ack if ... */
1843 /* just sent a rcv wnd 0
1844 || (tc->flags & TCP_CONN_SENT_RCV_WND0) != 0 */
1845 /* constrained to send ack */
1846 || (tc->flags & TCP_CONN_SNDACK) != 0
1847 /* we're almost out of tx wnd */
1848 || tcp_available_cc_snd_space (tc) < 4 * tc->snd_mss)
1855 tcp_buffer_discard_bytes (vlib_buffer_t * b, u32 n_bytes_to_drop)
1857 u32 discard, first = b->current_length;
1858 vlib_main_t *vm = vlib_get_main ();
1860 /* Handle multi-buffer segments */
1861 if (n_bytes_to_drop > b->current_length)
1863 if (!(b->flags & VLIB_BUFFER_NEXT_PRESENT))
1867 discard = clib_min (n_bytes_to_drop, b->current_length);
1868 vlib_buffer_advance (b, discard);
1869 b = vlib_get_buffer (vm, b->next_buffer);
1870 n_bytes_to_drop -= discard;
1872 while (n_bytes_to_drop);
1873 if (n_bytes_to_drop > first)
1874 b->total_length_not_including_first_buffer -= n_bytes_to_drop - first;
1877 vlib_buffer_advance (b, n_bytes_to_drop);
1878 vnet_buffer (b)->tcp.data_len -= n_bytes_to_drop;
1883 * Receive buffer for connection and handle acks
1885 * It handles both in order or out-of-order data.
1888 tcp_segment_rcv (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1891 u32 error, n_bytes_to_drop, n_data_bytes;
1893 vlib_buffer_advance (b, vnet_buffer (b)->tcp.data_offset);
1894 n_data_bytes = vnet_buffer (b)->tcp.data_len;
1895 ASSERT (n_data_bytes);
1896 tc->data_segs_in += 1;
1898 /* Handle out-of-order data */
1899 if (PREDICT_FALSE (vnet_buffer (b)->tcp.seq_number != tc->rcv_nxt))
1901 /* Old sequence numbers allowed through because they overlapped
1903 if (seq_lt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt))
1905 /* Completely in the past (possible retransmit). Ack
1906 * retransmissions since we may not have any data to send */
1907 if (seq_leq (vnet_buffer (b)->tcp.seq_end, tc->rcv_nxt))
1909 tcp_program_ack (tc);
1910 error = TCP_ERROR_SEGMENT_OLD;
1914 /* Chop off the bytes in the past and see if what is left
1915 * can be enqueued in order */
1916 n_bytes_to_drop = tc->rcv_nxt - vnet_buffer (b)->tcp.seq_number;
1917 n_data_bytes -= n_bytes_to_drop;
1918 vnet_buffer (b)->tcp.seq_number = tc->rcv_nxt;
1919 if (tcp_buffer_discard_bytes (b, n_bytes_to_drop))
1921 error = TCP_ERROR_SEGMENT_OLD;
1927 /* RFC2581: Enqueue and send DUPACK for fast retransmit */
1928 error = tcp_session_enqueue_ooo (tc, b, n_data_bytes);
1929 tcp_program_dupack (tc);
1930 TCP_EVT (TCP_EVT_DUPACK_SENT, tc, vnet_buffer (b)->tcp);
1931 tc->errors.above_data_wnd += seq_gt (vnet_buffer (b)->tcp.seq_end,
1932 tc->rcv_las + tc->rcv_wnd);
1938 /* In order data, enqueue. Fifo figures out by itself if any out-of-order
1939 * segments can be enqueued after fifo tail offset changes. */
1940 error = tcp_session_enqueue_data (tc, b, n_data_bytes);
1941 if (tcp_can_delack (tc))
1943 if (!tcp_timer_is_active (tc, TCP_TIMER_DELACK))
1944 tcp_timer_set (tc, TCP_TIMER_DELACK, tcp_cfg.delack_time);
1948 tcp_program_ack (tc);
1956 tcp_header_t tcp_header;
1957 tcp_connection_t tcp_connection;
1961 format_tcp_rx_trace (u8 * s, va_list * args)
1963 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1964 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1965 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
1966 u32 indent = format_get_indent (s);
1968 s = format (s, "%U\n%U%U",
1969 format_tcp_header, &t->tcp_header, 128,
1970 format_white_space, indent,
1971 format_tcp_connection, &t->tcp_connection, 1);
1977 format_tcp_rx_trace_short (u8 * s, va_list * args)
1979 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1980 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1981 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
1983 s = format (s, "%d -> %d (%U)",
1984 clib_net_to_host_u16 (t->tcp_header.dst_port),
1985 clib_net_to_host_u16 (t->tcp_header.src_port), format_tcp_state,
1986 t->tcp_connection.state);
1992 tcp_set_rx_trace_data (tcp_rx_trace_t * t0, tcp_connection_t * tc0,
1993 tcp_header_t * th0, vlib_buffer_t * b0, u8 is_ip4)
1997 clib_memcpy_fast (&t0->tcp_connection, tc0,
1998 sizeof (t0->tcp_connection));
2002 th0 = tcp_buffer_hdr (b0);
2004 clib_memcpy_fast (&t0->tcp_header, th0, sizeof (t0->tcp_header));
2008 tcp_established_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
2009 vlib_frame_t * frame, u8 is_ip4)
2013 n_left = frame->n_vectors;
2014 from = vlib_frame_vector_args (frame);
2018 tcp_connection_t *tc0;
2025 b0 = vlib_get_buffer (vm, bi0);
2027 if (b0->flags & VLIB_BUFFER_IS_TRACED)
2029 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2030 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
2032 th0 = tcp_buffer_hdr (b0);
2033 tcp_set_rx_trace_data (t0, tc0, th0, b0, is_ip4);
2042 tcp_node_inc_counter_i (vlib_main_t * vm, u32 tcp4_node, u32 tcp6_node,
2043 u8 is_ip4, u32 evt, u32 val)
2046 vlib_node_increment_counter (vm, tcp4_node, evt, val);
2048 vlib_node_increment_counter (vm, tcp6_node, evt, val);
2051 #define tcp_maybe_inc_counter(node_id, err, count) \
2053 if (next0 != tcp_next_drop (is_ip4)) \
2054 tcp_node_inc_counter_i (vm, tcp4_##node_id##_node.index, \
2055 tcp6_##node_id##_node.index, is_ip4, err, \
2058 #define tcp_inc_counter(node_id, err, count) \
2059 tcp_node_inc_counter_i (vm, tcp4_##node_id##_node.index, \
2060 tcp6_##node_id##_node.index, is_ip4, \
2062 #define tcp_maybe_inc_err_counter(cnts, err) \
2064 cnts[err] += (next0 != tcp_next_drop (is_ip4)); \
2066 #define tcp_inc_err_counter(cnts, err, val) \
2070 #define tcp_store_err_counters(node_id, cnts) \
2073 for (i = 0; i < TCP_N_ERROR; i++) \
2075 tcp_inc_counter(node_id, i, cnts[i]); \
2080 tcp46_established_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2081 vlib_frame_t * frame, int is_ip4)
2083 u32 thread_index = vm->thread_index, errors = 0;
2084 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
2085 u32 n_left_from, *from, *first_buffer;
2086 u16 err_counters[TCP_N_ERROR] = { 0 };
2088 if (node->flags & VLIB_NODE_FLAG_TRACE)
2089 tcp_established_trace_frame (vm, node, frame, is_ip4);
2091 first_buffer = from = vlib_frame_vector_args (frame);
2092 n_left_from = frame->n_vectors;
2094 while (n_left_from > 0)
2096 u32 bi0, error0 = TCP_ERROR_ACK_OK;
2099 tcp_connection_t *tc0;
2101 if (n_left_from > 1)
2104 pb = vlib_get_buffer (vm, from[1]);
2105 vlib_prefetch_buffer_header (pb, LOAD);
2106 CLIB_PREFETCH (pb->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2113 b0 = vlib_get_buffer (vm, bi0);
2114 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
2117 if (PREDICT_FALSE (tc0 == 0))
2119 error0 = TCP_ERROR_INVALID_CONNECTION;
2123 th0 = tcp_buffer_hdr (b0);
2125 /* TODO header prediction fast path */
2127 /* 1-4: check SEQ, RST, SYN */
2128 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc0, b0, th0, &error0)))
2130 TCP_EVT (TCP_EVT_SEG_INVALID, tc0, vnet_buffer (b0)->tcp);
2134 /* 5: check the ACK field */
2135 if (PREDICT_FALSE (tcp_rcv_ack (wrk, tc0, b0, th0, &error0)))
2138 /* 6: check the URG bit TODO */
2140 /* 7: process the segment text */
2141 if (vnet_buffer (b0)->tcp.data_len)
2142 error0 = tcp_segment_rcv (wrk, tc0, b0);
2144 /* 8: check the FIN bit */
2145 if (PREDICT_FALSE (tcp_is_fin (th0)))
2146 tcp_rcv_fin (wrk, tc0, b0, &error0);
2149 tcp_inc_err_counter (err_counters, error0, 1);
2152 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
2154 err_counters[TCP_ERROR_MSG_QUEUE_FULL] = errors;
2155 tcp_store_err_counters (established, err_counters);
2156 tcp_handle_postponed_dequeues (wrk);
2157 tcp_handle_disconnects (wrk);
2158 vlib_buffer_free (vm, first_buffer, frame->n_vectors);
2160 return frame->n_vectors;
2163 VLIB_NODE_FN (tcp4_established_node) (vlib_main_t * vm,
2164 vlib_node_runtime_t * node,
2165 vlib_frame_t * from_frame)
2167 return tcp46_established_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2170 VLIB_NODE_FN (tcp6_established_node) (vlib_main_t * vm,
2171 vlib_node_runtime_t * node,
2172 vlib_frame_t * from_frame)
2174 return tcp46_established_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2178 VLIB_REGISTER_NODE (tcp4_established_node) =
2180 .name = "tcp4-established",
2181 /* Takes a vector of packets. */
2182 .vector_size = sizeof (u32),
2183 .n_errors = TCP_N_ERROR,
2184 .error_strings = tcp_error_strings,
2185 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
2188 #define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
2189 foreach_tcp_state_next
2192 .format_trace = format_tcp_rx_trace_short,
2197 VLIB_REGISTER_NODE (tcp6_established_node) =
2199 .name = "tcp6-established",
2200 /* Takes a vector of packets. */
2201 .vector_size = sizeof (u32),
2202 .n_errors = TCP_N_ERROR,
2203 .error_strings = tcp_error_strings,
2204 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
2207 #define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
2208 foreach_tcp_state_next
2211 .format_trace = format_tcp_rx_trace_short,
2217 tcp_lookup_is_valid (tcp_connection_t * tc, tcp_header_t * hdr)
2219 transport_connection_t *tmp = 0;
2226 if (tc->c_lcl_port == 0 && tc->state == TCP_STATE_LISTEN)
2229 u8 is_valid = (tc->c_lcl_port == hdr->dst_port
2230 && (tc->state == TCP_STATE_LISTEN
2231 || tc->c_rmt_port == hdr->src_port));
2235 handle = session_lookup_half_open_handle (&tc->connection);
2236 tmp = session_lookup_half_open_connection (handle & 0xFFFFFFFF,
2237 tc->c_proto, tc->c_is_ip4);
2241 if (tmp->lcl_port == hdr->dst_port
2242 && tmp->rmt_port == hdr->src_port)
2244 TCP_DBG ("half-open is valid!");
2252 * Lookup transport connection
2254 static tcp_connection_t *
2255 tcp_lookup_connection (u32 fib_index, vlib_buffer_t * b, u8 thread_index,
2259 transport_connection_t *tconn;
2260 tcp_connection_t *tc;
2265 ip4 = vlib_buffer_get_current (b);
2266 tcp = ip4_next_header (ip4);
2267 tconn = session_lookup_connection_wt4 (fib_index,
2272 TRANSPORT_PROTO_TCP,
2273 thread_index, &is_filtered);
2274 tc = tcp_get_connection_from_transport (tconn);
2275 ASSERT (tcp_lookup_is_valid (tc, tcp));
2280 ip6 = vlib_buffer_get_current (b);
2281 tcp = ip6_next_header (ip6);
2282 tconn = session_lookup_connection_wt6 (fib_index,
2287 TRANSPORT_PROTO_TCP,
2288 thread_index, &is_filtered);
2289 tc = tcp_get_connection_from_transport (tconn);
2290 ASSERT (tcp_lookup_is_valid (tc, tcp));
2296 tcp46_syn_sent_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2297 vlib_frame_t * from_frame, int is_ip4)
2299 u32 n_left_from, *from, *first_buffer, errors = 0;
2300 u32 my_thread_index = vm->thread_index;
2301 tcp_worker_ctx_t *wrk = tcp_get_worker (my_thread_index);
2303 from = first_buffer = vlib_frame_vector_args (from_frame);
2304 n_left_from = from_frame->n_vectors;
2306 while (n_left_from > 0)
2308 u32 bi0, ack0, seq0, error0 = TCP_ERROR_NONE;
2309 tcp_connection_t *tc0, *new_tc0;
2310 tcp_header_t *tcp0 = 0;
2318 b0 = vlib_get_buffer (vm, bi0);
2320 tcp_half_open_connection_get (vnet_buffer (b0)->tcp.connection_index);
2321 if (PREDICT_FALSE (tc0 == 0))
2323 error0 = TCP_ERROR_INVALID_CONNECTION;
2327 /* Half-open completed recently but the connection was't removed
2328 * yet by the owning thread */
2329 if (PREDICT_FALSE (tc0->flags & TCP_CONN_HALF_OPEN_DONE))
2331 /* Make sure the connection actually exists */
2332 ASSERT (tcp_lookup_connection (tc0->c_fib_index, b0,
2333 my_thread_index, is_ip4));
2334 error0 = TCP_ERROR_SPURIOUS_SYN_ACK;
2338 ack0 = vnet_buffer (b0)->tcp.ack_number;
2339 seq0 = vnet_buffer (b0)->tcp.seq_number;
2340 tcp0 = tcp_buffer_hdr (b0);
2342 /* Crude check to see if the connection handle does not match
2343 * the packet. Probably connection just switched to established */
2344 if (PREDICT_FALSE (tcp0->dst_port != tc0->c_lcl_port
2345 || tcp0->src_port != tc0->c_rmt_port))
2347 error0 = TCP_ERROR_INVALID_CONNECTION;
2351 if (PREDICT_FALSE (!tcp_ack (tcp0) && !tcp_rst (tcp0)
2352 && !tcp_syn (tcp0)))
2354 error0 = TCP_ERROR_SEGMENT_INVALID;
2358 /* SYNs consume sequence numbers */
2359 vnet_buffer (b0)->tcp.seq_end += tcp_is_syn (tcp0);
2362 * 1. check the ACK bit
2366 * If the ACK bit is set
2367 * If SEG.ACK =< ISS, or SEG.ACK > SND.NXT, send a reset (unless
2368 * the RST bit is set, if so drop the segment and return)
2369 * <SEQ=SEG.ACK><CTL=RST>
2370 * and discard the segment. Return.
2371 * If SND.UNA =< SEG.ACK =< SND.NXT then the ACK is acceptable.
2375 if (seq_leq (ack0, tc0->iss) || seq_gt (ack0, tc0->snd_nxt))
2377 if (!tcp_rst (tcp0))
2378 tcp_send_reset_w_pkt (tc0, b0, my_thread_index, is_ip4);
2379 error0 = TCP_ERROR_RCV_WND;
2383 /* Make sure ACK is valid */
2384 if (seq_gt (tc0->snd_una, ack0))
2386 error0 = TCP_ERROR_ACK_INVALID;
2392 * 2. check the RST bit
2397 /* If ACK is acceptable, signal client that peer is not
2398 * willing to accept connection and drop connection*/
2400 tcp_connection_reset (tc0);
2401 error0 = TCP_ERROR_RST_RCVD;
2406 * 3. check the security and precedence (skipped)
2410 * 4. check the SYN bit
2413 /* No SYN flag. Drop. */
2414 if (!tcp_syn (tcp0))
2416 error0 = TCP_ERROR_SEGMENT_INVALID;
2421 if (tcp_options_parse (tcp0, &tc0->rcv_opts, 1))
2423 error0 = TCP_ERROR_OPTIONS;
2427 /* Valid SYN or SYN-ACK. Move connection from half-open pool to
2428 * current thread pool. */
2429 new_tc0 = tcp_connection_alloc_w_base (my_thread_index, tc0);
2430 new_tc0->rcv_nxt = vnet_buffer (b0)->tcp.seq_end;
2431 new_tc0->irs = seq0;
2432 new_tc0->timers[TCP_TIMER_RETRANSMIT_SYN] = TCP_TIMER_HANDLE_INVALID;
2433 new_tc0->sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX];
2435 /* If this is not the owning thread, wait for syn retransmit to
2436 * expire and cleanup then */
2437 if (tcp_half_open_connection_cleanup (tc0))
2438 tc0->flags |= TCP_CONN_HALF_OPEN_DONE;
2440 if (tcp_opts_tstamp (&new_tc0->rcv_opts))
2442 new_tc0->tsval_recent = new_tc0->rcv_opts.tsval;
2443 new_tc0->tsval_recent_age = tcp_time_now ();
2446 if (tcp_opts_wscale (&new_tc0->rcv_opts))
2447 new_tc0->snd_wscale = new_tc0->rcv_opts.wscale;
2449 new_tc0->rcv_wscale = 0;
2451 new_tc0->snd_wnd = clib_net_to_host_u16 (tcp0->window)
2452 << new_tc0->snd_wscale;
2453 new_tc0->snd_wl1 = seq0;
2454 new_tc0->snd_wl2 = ack0;
2456 tcp_connection_init_vars (new_tc0);
2458 /* SYN-ACK: See if we can switch to ESTABLISHED state */
2459 if (PREDICT_TRUE (tcp_ack (tcp0)))
2461 /* Our SYN is ACKed: we have iss < ack = snd_una */
2463 /* TODO Dequeue acknowledged segments if we support Fast Open */
2464 new_tc0->snd_una = ack0;
2465 new_tc0->state = TCP_STATE_ESTABLISHED;
2467 /* Make sure las is initialized for the wnd computation */
2468 new_tc0->rcv_las = new_tc0->rcv_nxt;
2470 /* Notify app that we have connection. If session layer can't
2471 * allocate session send reset */
2472 if (session_stream_connect_notify (&new_tc0->connection, 0))
2474 tcp_send_reset_w_pkt (new_tc0, b0, my_thread_index, is_ip4);
2475 tcp_connection_cleanup (new_tc0);
2476 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
2480 new_tc0->tx_fifo_size =
2481 transport_tx_fifo_size (&new_tc0->connection);
2482 /* Update rtt with the syn-ack sample */
2483 tcp_estimate_initial_rtt (new_tc0);
2484 TCP_EVT (TCP_EVT_SYNACK_RCVD, new_tc0);
2485 error0 = TCP_ERROR_SYN_ACKS_RCVD;
2487 /* SYN: Simultaneous open. Change state to SYN-RCVD and send SYN-ACK */
2490 new_tc0->state = TCP_STATE_SYN_RCVD;
2492 /* Notify app that we have connection */
2493 if (session_stream_connect_notify (&new_tc0->connection, 0))
2495 tcp_connection_cleanup (new_tc0);
2496 tcp_send_reset_w_pkt (tc0, b0, my_thread_index, is_ip4);
2497 TCP_EVT (TCP_EVT_RST_SENT, tc0);
2498 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
2502 new_tc0->tx_fifo_size =
2503 transport_tx_fifo_size (&new_tc0->connection);
2504 new_tc0->rtt_ts = 0;
2505 tcp_init_snd_vars (new_tc0);
2506 tcp_send_synack (new_tc0);
2507 error0 = TCP_ERROR_SYNS_RCVD;
2511 /* Read data, if any */
2512 if (PREDICT_FALSE (vnet_buffer (b0)->tcp.data_len))
2514 clib_warning ("rcvd data in syn-sent");
2515 error0 = tcp_segment_rcv (wrk, new_tc0, b0);
2516 if (error0 == TCP_ERROR_ACK_OK)
2517 error0 = TCP_ERROR_SYN_ACKS_RCVD;
2521 tcp_program_ack (new_tc0);
2526 tcp_inc_counter (syn_sent, error0, 1);
2527 if (PREDICT_FALSE ((b0->flags & VLIB_BUFFER_IS_TRACED) && tcp0 != 0))
2529 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2530 clib_memcpy_fast (&t0->tcp_header, tcp0, sizeof (t0->tcp_header));
2531 clib_memcpy_fast (&t0->tcp_connection, tc0,
2532 sizeof (t0->tcp_connection));
2536 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
2538 tcp_inc_counter (syn_sent, TCP_ERROR_MSG_QUEUE_FULL, errors);
2539 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
2541 return from_frame->n_vectors;
2544 VLIB_NODE_FN (tcp4_syn_sent_node) (vlib_main_t * vm,
2545 vlib_node_runtime_t * node,
2546 vlib_frame_t * from_frame)
2548 return tcp46_syn_sent_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2551 VLIB_NODE_FN (tcp6_syn_sent_node) (vlib_main_t * vm,
2552 vlib_node_runtime_t * node,
2553 vlib_frame_t * from_frame)
2555 return tcp46_syn_sent_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2559 VLIB_REGISTER_NODE (tcp4_syn_sent_node) =
2561 .name = "tcp4-syn-sent",
2562 /* Takes a vector of packets. */
2563 .vector_size = sizeof (u32),
2564 .n_errors = TCP_N_ERROR,
2565 .error_strings = tcp_error_strings,
2566 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2569 #define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2570 foreach_tcp_state_next
2573 .format_trace = format_tcp_rx_trace_short,
2578 VLIB_REGISTER_NODE (tcp6_syn_sent_node) =
2580 .name = "tcp6-syn-sent",
2581 /* Takes a vector of packets. */
2582 .vector_size = sizeof (u32),
2583 .n_errors = TCP_N_ERROR,
2584 .error_strings = tcp_error_strings,
2585 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2588 #define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2589 foreach_tcp_state_next
2592 .format_trace = format_tcp_rx_trace_short,
2597 * Handles reception for all states except LISTEN, SYN-SENT and ESTABLISHED
2598 * as per RFC793 p. 64
2601 tcp46_rcv_process_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2602 vlib_frame_t * from_frame, int is_ip4)
2604 u32 thread_index = vm->thread_index, errors = 0, *first_buffer;
2605 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
2606 u32 n_left_from, *from, max_dequeue;
2608 from = first_buffer = vlib_frame_vector_args (from_frame);
2609 n_left_from = from_frame->n_vectors;
2611 while (n_left_from > 0)
2613 u32 bi0, error0 = TCP_ERROR_NONE;
2614 tcp_header_t *tcp0 = 0;
2615 tcp_connection_t *tc0;
2623 b0 = vlib_get_buffer (vm, bi0);
2624 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
2626 if (PREDICT_FALSE (tc0 == 0))
2628 error0 = TCP_ERROR_INVALID_CONNECTION;
2632 tcp0 = tcp_buffer_hdr (b0);
2633 is_fin0 = tcp_is_fin (tcp0);
2637 tcp_connection_t *tmp;
2638 tmp = tcp_lookup_connection (tc0->c_fib_index, b0, thread_index,
2640 if (tmp->state != tc0->state)
2642 if (tc0->state != TCP_STATE_CLOSED)
2643 clib_warning ("state changed");
2649 * Special treatment for CLOSED
2651 if (PREDICT_FALSE (tc0->state == TCP_STATE_CLOSED))
2653 error0 = TCP_ERROR_CONNECTION_CLOSED;
2658 * For all other states (except LISTEN)
2661 /* 1-4: check SEQ, RST, SYN */
2662 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc0, b0, tcp0, &error0)))
2665 /* 5: check the ACK field */
2668 case TCP_STATE_SYN_RCVD:
2670 /* Make sure the segment is exactly right */
2671 if (tc0->rcv_nxt != vnet_buffer (b0)->tcp.seq_number || is_fin0)
2673 tcp_connection_reset (tc0);
2674 error0 = TCP_ERROR_SEGMENT_INVALID;
2679 * If the segment acknowledgment is not acceptable, form a
2681 * <SEQ=SEG.ACK><CTL=RST>
2684 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2686 tcp_connection_reset (tc0);
2690 /* Update rtt and rto */
2691 tcp_estimate_initial_rtt (tc0);
2693 /* Switch state to ESTABLISHED */
2694 tc0->state = TCP_STATE_ESTABLISHED;
2695 TCP_EVT (TCP_EVT_STATE_CHANGE, tc0);
2697 /* Initialize session variables */
2698 tc0->snd_una = vnet_buffer (b0)->tcp.ack_number;
2699 tc0->snd_wnd = clib_net_to_host_u16 (tcp0->window)
2700 << tc0->rcv_opts.wscale;
2701 tc0->snd_wl1 = vnet_buffer (b0)->tcp.seq_number;
2702 tc0->snd_wl2 = vnet_buffer (b0)->tcp.ack_number;
2704 /* Reset SYN-ACK retransmit and SYN_RCV establish timers */
2705 tcp_retransmit_timer_reset (tc0);
2706 if (session_stream_accept_notify (&tc0->connection))
2708 error0 = TCP_ERROR_MSG_QUEUE_FULL;
2709 tcp_connection_reset (tc0);
2712 error0 = TCP_ERROR_ACK_OK;
2714 case TCP_STATE_ESTABLISHED:
2715 /* We can get packets in established state here because they
2716 * were enqueued before state change */
2717 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2721 case TCP_STATE_FIN_WAIT_1:
2722 /* In addition to the processing for the ESTABLISHED state, if
2723 * our FIN is now acknowledged then enter FIN-WAIT-2 and
2724 * continue processing in that state. */
2725 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2728 /* Still have to send the FIN */
2729 if (tc0->flags & TCP_CONN_FINPNDG)
2731 /* TX fifo finally drained */
2732 max_dequeue = transport_max_tx_dequeue (&tc0->connection);
2733 if (max_dequeue <= tc0->burst_acked)
2735 /* If a fin was received and data was acked extend wait */
2736 else if ((tc0->flags & TCP_CONN_FINRCVD) && tc0->bytes_acked)
2737 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE,
2738 tcp_cfg.closewait_time);
2740 /* If FIN is ACKed */
2741 else if (tc0->snd_una == tc0->snd_nxt)
2743 /* Stop all retransmit timers because we have nothing more
2745 tcp_connection_timers_reset (tc0);
2747 /* We already have a FIN but didn't transition to CLOSING
2748 * because of outstanding tx data. Close the connection. */
2749 if (tc0->flags & TCP_CONN_FINRCVD)
2751 tcp_connection_set_state (tc0, TCP_STATE_CLOSED);
2752 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE,
2753 tcp_cfg.cleanup_time);
2754 session_transport_closed_notify (&tc0->connection);
2758 tcp_connection_set_state (tc0, TCP_STATE_FIN_WAIT_2);
2759 /* Enable waitclose because we're willing to wait for peer's
2760 * FIN but not indefinitely. */
2761 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.finwait2_time);
2763 /* Don't try to deq the FIN acked */
2764 if (tc0->burst_acked > 1)
2765 session_tx_fifo_dequeue_drop (&tc0->connection,
2766 tc0->burst_acked - 1);
2767 tc0->burst_acked = 0;
2770 case TCP_STATE_FIN_WAIT_2:
2771 /* In addition to the processing for the ESTABLISHED state, if
2772 * the retransmission queue is empty, the user's CLOSE can be
2773 * acknowledged ("ok") but do not delete the TCB. */
2774 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2776 tc0->burst_acked = 0;
2778 case TCP_STATE_CLOSE_WAIT:
2779 /* Do the same processing as for the ESTABLISHED state. */
2780 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2783 if (!(tc0->flags & TCP_CONN_FINPNDG))
2786 /* Still have outstanding tx data */
2787 max_dequeue = transport_max_tx_dequeue (&tc0->connection);
2788 if (max_dequeue > tc0->burst_acked)
2792 tcp_connection_timers_reset (tc0);
2793 tcp_connection_set_state (tc0, TCP_STATE_LAST_ACK);
2794 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.lastack_time);
2796 case TCP_STATE_CLOSING:
2797 /* In addition to the processing for the ESTABLISHED state, if
2798 * the ACK acknowledges our FIN then enter the TIME-WAIT state,
2799 * otherwise ignore the segment. */
2800 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2803 if (tc0->snd_una != tc0->snd_nxt)
2806 tcp_connection_timers_reset (tc0);
2807 tcp_connection_set_state (tc0, TCP_STATE_TIME_WAIT);
2808 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.timewait_time);
2809 session_transport_closed_notify (&tc0->connection);
2813 case TCP_STATE_LAST_ACK:
2814 /* The only thing that [should] arrive in this state is an
2815 * acknowledgment of our FIN. If our FIN is now acknowledged,
2816 * delete the TCB, enter the CLOSED state, and return. */
2818 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2821 /* Apparently our ACK for the peer's FIN was lost */
2822 if (is_fin0 && tc0->snd_una != tc0->snd_nxt)
2828 tcp_connection_set_state (tc0, TCP_STATE_CLOSED);
2829 session_transport_closed_notify (&tc0->connection);
2831 /* Don't free the connection from the data path since
2832 * we can't ensure that we have no packets already enqueued
2833 * to output. Rely instead on the waitclose timer */
2834 tcp_connection_timers_reset (tc0);
2835 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.cleanup_time);
2840 case TCP_STATE_TIME_WAIT:
2841 /* The only thing that can arrive in this state is a
2842 * retransmission of the remote FIN. Acknowledge it, and restart
2843 * the 2 MSL timeout. */
2845 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2851 tcp_program_ack (tc0);
2852 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.timewait_time);
2860 /* 6: check the URG bit TODO */
2862 /* 7: process the segment text */
2865 case TCP_STATE_ESTABLISHED:
2866 case TCP_STATE_FIN_WAIT_1:
2867 case TCP_STATE_FIN_WAIT_2:
2868 if (vnet_buffer (b0)->tcp.data_len)
2869 error0 = tcp_segment_rcv (wrk, tc0, b0);
2871 case TCP_STATE_CLOSE_WAIT:
2872 case TCP_STATE_CLOSING:
2873 case TCP_STATE_LAST_ACK:
2874 case TCP_STATE_TIME_WAIT:
2875 /* This should not occur, since a FIN has been received from the
2876 * remote side. Ignore the segment text. */
2880 /* 8: check the FIN bit */
2884 TCP_EVT (TCP_EVT_FIN_RCVD, tc0);
2888 case TCP_STATE_ESTABLISHED:
2889 /* Account for the FIN and send ack */
2891 tcp_program_ack (tc0);
2892 tcp_connection_set_state (tc0, TCP_STATE_CLOSE_WAIT);
2893 tcp_program_disconnect (wrk, tc0);
2894 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.closewait_time);
2896 case TCP_STATE_SYN_RCVD:
2897 /* Send FIN-ACK, enter LAST-ACK and because the app was not
2898 * notified yet, set a cleanup timer instead of relying on
2899 * disconnect notify and the implicit close call. */
2900 tcp_connection_timers_reset (tc0);
2903 tcp_connection_set_state (tc0, TCP_STATE_LAST_ACK);
2904 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.lastack_time);
2906 case TCP_STATE_CLOSE_WAIT:
2907 case TCP_STATE_CLOSING:
2908 case TCP_STATE_LAST_ACK:
2911 case TCP_STATE_FIN_WAIT_1:
2914 if (tc0->flags & TCP_CONN_FINPNDG)
2916 /* If data is outstanding, stay in FIN_WAIT_1 and try to finish
2917 * sending it. Since we already received a fin, do not wait
2919 tc0->flags |= TCP_CONN_FINRCVD;
2920 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE,
2921 tcp_cfg.closewait_time);
2925 tcp_connection_set_state (tc0, TCP_STATE_CLOSING);
2926 tcp_program_ack (tc0);
2927 /* Wait for ACK for our FIN but not forever */
2928 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE,
2929 tcp_cfg.closing_time);
2932 case TCP_STATE_FIN_WAIT_2:
2933 /* Got FIN, send ACK! Be more aggressive with resource cleanup */
2935 tcp_connection_set_state (tc0, TCP_STATE_TIME_WAIT);
2936 tcp_connection_timers_reset (tc0);
2937 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.timewait_time);
2938 tcp_program_ack (tc0);
2939 session_transport_closed_notify (&tc0->connection);
2941 case TCP_STATE_TIME_WAIT:
2942 /* Remain in the TIME-WAIT state. Restart the time-wait
2945 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.timewait_time);
2948 error0 = TCP_ERROR_FIN_RCVD;
2952 tcp_inc_counter (rcv_process, error0, 1);
2953 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
2955 tcp_rx_trace_t *t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2956 tcp_set_rx_trace_data (t0, tc0, tcp0, b0, is_ip4);
2960 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
2962 tcp_inc_counter (rcv_process, TCP_ERROR_MSG_QUEUE_FULL, errors);
2963 tcp_handle_postponed_dequeues (wrk);
2964 tcp_handle_disconnects (wrk);
2965 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
2967 return from_frame->n_vectors;
2970 VLIB_NODE_FN (tcp4_rcv_process_node) (vlib_main_t * vm,
2971 vlib_node_runtime_t * node,
2972 vlib_frame_t * from_frame)
2974 return tcp46_rcv_process_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2977 VLIB_NODE_FN (tcp6_rcv_process_node) (vlib_main_t * vm,
2978 vlib_node_runtime_t * node,
2979 vlib_frame_t * from_frame)
2981 return tcp46_rcv_process_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2985 VLIB_REGISTER_NODE (tcp4_rcv_process_node) =
2987 .name = "tcp4-rcv-process",
2988 /* Takes a vector of packets. */
2989 .vector_size = sizeof (u32),
2990 .n_errors = TCP_N_ERROR,
2991 .error_strings = tcp_error_strings,
2992 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
2995 #define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
2996 foreach_tcp_state_next
2999 .format_trace = format_tcp_rx_trace_short,
3004 VLIB_REGISTER_NODE (tcp6_rcv_process_node) =
3006 .name = "tcp6-rcv-process",
3007 /* Takes a vector of packets. */
3008 .vector_size = sizeof (u32),
3009 .n_errors = TCP_N_ERROR,
3010 .error_strings = tcp_error_strings,
3011 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
3014 #define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
3015 foreach_tcp_state_next
3018 .format_trace = format_tcp_rx_trace_short,
3023 * LISTEN state processing as per RFC 793 p. 65
3026 tcp46_listen_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
3027 vlib_frame_t * from_frame, int is_ip4)
3029 u32 n_left_from, *from, n_syns = 0, *first_buffer;
3030 u32 my_thread_index = vm->thread_index;
3032 from = first_buffer = vlib_frame_vector_args (from_frame);
3033 n_left_from = from_frame->n_vectors;
3035 while (n_left_from > 0)
3040 tcp_header_t *th0 = 0;
3041 tcp_connection_t *lc0;
3044 tcp_connection_t *child0;
3045 u32 error0 = TCP_ERROR_NONE;
3051 b0 = vlib_get_buffer (vm, bi0);
3052 lc0 = tcp_listener_get (vnet_buffer (b0)->tcp.connection_index);
3056 ip40 = vlib_buffer_get_current (b0);
3057 th0 = ip4_next_header (ip40);
3061 ip60 = vlib_buffer_get_current (b0);
3062 th0 = ip6_next_header (ip60);
3065 /* Create child session. For syn-flood protection use filter */
3067 /* 1. first check for an RST: handled in dispatch */
3068 /* if (tcp_rst (th0))
3072 /* 2. second check for an ACK: handled in dispatch */
3073 /* if (tcp_ack (th0))
3075 tcp_send_reset (b0, is_ip4);
3080 /* 3. check for a SYN (did that already) */
3082 /* Make sure connection wasn't just created */
3083 child0 = tcp_lookup_connection (lc0->c_fib_index, b0, my_thread_index,
3085 if (PREDICT_FALSE (child0->state != TCP_STATE_LISTEN))
3087 error0 = TCP_ERROR_CREATE_EXISTS;
3091 /* Create child session and send SYN-ACK */
3092 child0 = tcp_connection_alloc (my_thread_index);
3093 child0->c_lcl_port = th0->dst_port;
3094 child0->c_rmt_port = th0->src_port;
3095 child0->c_is_ip4 = is_ip4;
3096 child0->state = TCP_STATE_SYN_RCVD;
3097 child0->c_fib_index = lc0->c_fib_index;
3098 child0->cc_algo = lc0->cc_algo;
3102 child0->c_lcl_ip4.as_u32 = ip40->dst_address.as_u32;
3103 child0->c_rmt_ip4.as_u32 = ip40->src_address.as_u32;
3107 clib_memcpy_fast (&child0->c_lcl_ip6, &ip60->dst_address,
3108 sizeof (ip6_address_t));
3109 clib_memcpy_fast (&child0->c_rmt_ip6, &ip60->src_address,
3110 sizeof (ip6_address_t));
3113 if (tcp_options_parse (th0, &child0->rcv_opts, 1))
3115 error0 = TCP_ERROR_OPTIONS;
3116 tcp_connection_free (child0);
3120 child0->irs = vnet_buffer (b0)->tcp.seq_number;
3121 child0->rcv_nxt = vnet_buffer (b0)->tcp.seq_number + 1;
3122 child0->rcv_las = child0->rcv_nxt;
3123 child0->sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX];
3125 /* RFC1323: TSval timestamps sent on {SYN} and {SYN,ACK}
3126 * segments are used to initialize PAWS. */
3127 if (tcp_opts_tstamp (&child0->rcv_opts))
3129 child0->tsval_recent = child0->rcv_opts.tsval;
3130 child0->tsval_recent_age = tcp_time_now ();
3133 if (tcp_opts_wscale (&child0->rcv_opts))
3134 child0->snd_wscale = child0->rcv_opts.wscale;
3136 child0->snd_wnd = clib_net_to_host_u16 (th0->window)
3137 << child0->snd_wscale;
3138 child0->snd_wl1 = vnet_buffer (b0)->tcp.seq_number;
3139 child0->snd_wl2 = vnet_buffer (b0)->tcp.ack_number;
3141 tcp_connection_init_vars (child0);
3142 child0->rto = TCP_RTO_MIN;
3144 if (session_stream_accept (&child0->connection, lc0->c_s_index,
3145 lc0->c_thread_index, 0 /* notify */ ))
3147 tcp_connection_cleanup (child0);
3148 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
3152 TCP_EVT (TCP_EVT_SYN_RCVD, child0, 1);
3153 child0->tx_fifo_size = transport_tx_fifo_size (&child0->connection);
3154 tcp_send_synack (child0);
3158 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
3160 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
3161 clib_memcpy_fast (&t0->tcp_header, th0, sizeof (t0->tcp_header));
3162 clib_memcpy_fast (&t0->tcp_connection, lc0,
3163 sizeof (t0->tcp_connection));
3166 n_syns += (error0 == TCP_ERROR_NONE);
3169 tcp_inc_counter (listen, TCP_ERROR_SYNS_RCVD, n_syns);
3170 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
3172 return from_frame->n_vectors;
3175 VLIB_NODE_FN (tcp4_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3176 vlib_frame_t * from_frame)
3178 return tcp46_listen_inline (vm, node, from_frame, 1 /* is_ip4 */ );
3181 VLIB_NODE_FN (tcp6_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3182 vlib_frame_t * from_frame)
3184 return tcp46_listen_inline (vm, node, from_frame, 0 /* is_ip4 */ );
3188 VLIB_REGISTER_NODE (tcp4_listen_node) =
3190 .name = "tcp4-listen",
3191 /* Takes a vector of packets. */
3192 .vector_size = sizeof (u32),
3193 .n_errors = TCP_N_ERROR,
3194 .error_strings = tcp_error_strings,
3195 .n_next_nodes = TCP_LISTEN_N_NEXT,
3198 #define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
3199 foreach_tcp_state_next
3202 .format_trace = format_tcp_rx_trace_short,
3207 VLIB_REGISTER_NODE (tcp6_listen_node) =
3209 .name = "tcp6-listen",
3210 /* Takes a vector of packets. */
3211 .vector_size = sizeof (u32),
3212 .n_errors = TCP_N_ERROR,
3213 .error_strings = tcp_error_strings,
3214 .n_next_nodes = TCP_LISTEN_N_NEXT,
3217 #define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
3218 foreach_tcp_state_next
3221 .format_trace = format_tcp_rx_trace_short,
3225 typedef enum _tcp_input_next
3227 TCP_INPUT_NEXT_DROP,
3228 TCP_INPUT_NEXT_LISTEN,
3229 TCP_INPUT_NEXT_RCV_PROCESS,
3230 TCP_INPUT_NEXT_SYN_SENT,
3231 TCP_INPUT_NEXT_ESTABLISHED,
3232 TCP_INPUT_NEXT_RESET,
3233 TCP_INPUT_NEXT_PUNT,
3237 #define foreach_tcp4_input_next \
3238 _ (DROP, "ip4-drop") \
3239 _ (LISTEN, "tcp4-listen") \
3240 _ (RCV_PROCESS, "tcp4-rcv-process") \
3241 _ (SYN_SENT, "tcp4-syn-sent") \
3242 _ (ESTABLISHED, "tcp4-established") \
3243 _ (RESET, "tcp4-reset") \
3244 _ (PUNT, "ip4-punt")
3246 #define foreach_tcp6_input_next \
3247 _ (DROP, "ip6-drop") \
3248 _ (LISTEN, "tcp6-listen") \
3249 _ (RCV_PROCESS, "tcp6-rcv-process") \
3250 _ (SYN_SENT, "tcp6-syn-sent") \
3251 _ (ESTABLISHED, "tcp6-established") \
3252 _ (RESET, "tcp6-reset") \
3253 _ (PUNT, "ip6-punt")
3255 #define filter_flags (TCP_FLAG_SYN|TCP_FLAG_ACK|TCP_FLAG_RST|TCP_FLAG_FIN)
3258 tcp_input_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
3259 vlib_buffer_t ** bs, u32 n_bufs, u8 is_ip4)
3261 tcp_connection_t *tc;
3266 for (i = 0; i < n_bufs; i++)
3268 if (bs[i]->flags & VLIB_BUFFER_IS_TRACED)
3270 t = vlib_add_trace (vm, node, bs[i], sizeof (*t));
3271 tc = tcp_connection_get (vnet_buffer (bs[i])->tcp.connection_index,
3273 tcp = vlib_buffer_get_current (bs[i]);
3274 tcp_set_rx_trace_data (t, tc, tcp, bs[i], is_ip4);
3280 tcp_input_set_error_next (tcp_main_t * tm, u16 * next, u32 * error, u8 is_ip4)
3282 if (*error == TCP_ERROR_FILTERED || *error == TCP_ERROR_WRONG_THREAD)
3284 *next = TCP_INPUT_NEXT_DROP;
3286 else if ((is_ip4 && tm->punt_unknown4) || (!is_ip4 && tm->punt_unknown6))
3288 *next = TCP_INPUT_NEXT_PUNT;
3289 *error = TCP_ERROR_PUNT;
3293 *next = TCP_INPUT_NEXT_RESET;
3294 *error = TCP_ERROR_NO_LISTENER;
3298 always_inline tcp_connection_t *
3299 tcp_input_lookup_buffer (vlib_buffer_t * b, u8 thread_index, u32 * error,
3300 u8 is_ip4, u8 is_nolookup)
3302 u32 fib_index = vnet_buffer (b)->ip.fib_index;
3303 int n_advance_bytes, n_data_bytes;
3304 transport_connection_t *tc;
3310 ip4_header_t *ip4 = vlib_buffer_get_current (b);
3311 int ip_hdr_bytes = ip4_header_bytes (ip4);
3312 if (PREDICT_FALSE (b->current_length < ip_hdr_bytes + sizeof (*tcp)))
3314 *error = TCP_ERROR_LENGTH;
3317 tcp = ip4_next_header (ip4);
3318 vnet_buffer (b)->tcp.hdr_offset = (u8 *) tcp - (u8 *) ip4;
3319 n_advance_bytes = (ip_hdr_bytes + tcp_header_bytes (tcp));
3320 n_data_bytes = clib_net_to_host_u16 (ip4->length) - n_advance_bytes;
3322 /* Length check. Checksum computed by ipx_local no need to compute again */
3323 if (PREDICT_FALSE (n_data_bytes < 0))
3325 *error = TCP_ERROR_LENGTH;
3330 tc = session_lookup_connection_wt4 (fib_index, &ip4->dst_address,
3331 &ip4->src_address, tcp->dst_port,
3333 TRANSPORT_PROTO_TCP, thread_index,
3338 ip6_header_t *ip6 = vlib_buffer_get_current (b);
3339 if (PREDICT_FALSE (b->current_length < sizeof (*ip6) + sizeof (*tcp)))
3341 *error = TCP_ERROR_LENGTH;
3344 tcp = ip6_next_header (ip6);
3345 vnet_buffer (b)->tcp.hdr_offset = (u8 *) tcp - (u8 *) ip6;
3346 n_advance_bytes = tcp_header_bytes (tcp);
3347 n_data_bytes = clib_net_to_host_u16 (ip6->payload_length)
3349 n_advance_bytes += sizeof (ip6[0]);
3351 if (PREDICT_FALSE (n_data_bytes < 0))
3353 *error = TCP_ERROR_LENGTH;
3360 (ip6_address_is_link_local_unicast (&ip6->dst_address)))
3362 ip4_main_t *im = &ip4_main;
3363 fib_index = vec_elt (im->fib_index_by_sw_if_index,
3364 vnet_buffer (b)->sw_if_index[VLIB_RX]);
3367 tc = session_lookup_connection_wt6 (fib_index, &ip6->dst_address,
3369 tcp->dst_port, tcp->src_port,
3370 TRANSPORT_PROTO_TCP,
3371 thread_index, &result);
3377 (transport_connection_t *) tcp_connection_get (vnet_buffer (b)->
3378 tcp.connection_index,
3381 vnet_buffer (b)->tcp.seq_number = clib_net_to_host_u32 (tcp->seq_number);
3382 vnet_buffer (b)->tcp.ack_number = clib_net_to_host_u32 (tcp->ack_number);
3383 vnet_buffer (b)->tcp.data_offset = n_advance_bytes;
3384 vnet_buffer (b)->tcp.data_len = n_data_bytes;
3385 vnet_buffer (b)->tcp.seq_end = vnet_buffer (b)->tcp.seq_number
3387 vnet_buffer (b)->tcp.flags = 0;
3389 *error = result ? TCP_ERROR_NONE + result : *error;
3391 return tcp_get_connection_from_transport (tc);
3395 tcp_input_dispatch_buffer (tcp_main_t * tm, tcp_connection_t * tc,
3396 vlib_buffer_t * b, u16 * next, u32 * error)
3401 tcp = tcp_buffer_hdr (b);
3402 flags = tcp->flags & filter_flags;
3403 *next = tm->dispatch_table[tc->state][flags].next;
3404 *error = tm->dispatch_table[tc->state][flags].error;
3407 if (PREDICT_FALSE (*error == TCP_ERROR_DISPATCH
3408 || *next == TCP_INPUT_NEXT_RESET))
3410 /* Overload tcp flags to store state */
3411 tcp_state_t state = tc->state;
3412 vnet_buffer (b)->tcp.flags = tc->state;
3414 if (*error == TCP_ERROR_DISPATCH)
3415 clib_warning ("tcp conn %u disp error state %U flags %U",
3416 tc->c_c_index, format_tcp_state, state,
3417 format_tcp_flags, (int) flags);
3422 tcp46_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
3423 vlib_frame_t * frame, int is_ip4, u8 is_nolookup)
3425 u32 n_left_from, *from, thread_index = vm->thread_index;
3426 tcp_main_t *tm = vnet_get_tcp_main ();
3427 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
3428 u16 nexts[VLIB_FRAME_SIZE], *next;
3430 tcp_set_time_now (tcp_get_worker (thread_index));
3432 from = vlib_frame_vector_args (frame);
3433 n_left_from = frame->n_vectors;
3434 vlib_get_buffers (vm, from, bufs, n_left_from);
3439 while (n_left_from >= 4)
3441 u32 error0 = TCP_ERROR_NO_LISTENER, error1 = TCP_ERROR_NO_LISTENER;
3442 tcp_connection_t *tc0, *tc1;
3445 vlib_prefetch_buffer_header (b[2], STORE);
3446 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
3448 vlib_prefetch_buffer_header (b[3], STORE);
3449 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
3452 next[0] = next[1] = TCP_INPUT_NEXT_DROP;
3454 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
3456 tc1 = tcp_input_lookup_buffer (b[1], thread_index, &error1, is_ip4,
3459 if (PREDICT_TRUE (!tc0 + !tc1 == 0))
3461 ASSERT (tcp_lookup_is_valid (tc0, tcp_buffer_hdr (b[0])));
3462 ASSERT (tcp_lookup_is_valid (tc1, tcp_buffer_hdr (b[1])));
3464 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
3465 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
3467 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], &error0);
3468 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], &error1);
3472 if (PREDICT_TRUE (tc0 != 0))
3474 ASSERT (tcp_lookup_is_valid (tc0, tcp_buffer_hdr (b[0])));
3475 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
3476 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], &error0);
3479 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
3481 if (PREDICT_TRUE (tc1 != 0))
3483 ASSERT (tcp_lookup_is_valid (tc1, tcp_buffer_hdr (b[1])));
3484 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
3485 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], &error1);
3488 tcp_input_set_error_next (tm, &next[1], &error1, is_ip4);
3495 while (n_left_from > 0)
3497 tcp_connection_t *tc0;
3498 u32 error0 = TCP_ERROR_NO_LISTENER;
3500 if (n_left_from > 1)
3502 vlib_prefetch_buffer_header (b[1], STORE);
3503 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
3506 next[0] = TCP_INPUT_NEXT_DROP;
3507 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
3509 if (PREDICT_TRUE (tc0 != 0))
3511 ASSERT (tcp_lookup_is_valid (tc0, tcp_buffer_hdr (b[0])));
3512 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
3513 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], &error0);
3516 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
3523 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
3524 tcp_input_trace_frame (vm, node, bufs, frame->n_vectors, is_ip4);
3526 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
3527 return frame->n_vectors;
3530 VLIB_NODE_FN (tcp4_input_nolookup_node) (vlib_main_t * vm,
3531 vlib_node_runtime_t * node,
3532 vlib_frame_t * from_frame)
3534 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
3535 1 /* is_nolookup */ );
3538 VLIB_NODE_FN (tcp6_input_nolookup_node) (vlib_main_t * vm,
3539 vlib_node_runtime_t * node,
3540 vlib_frame_t * from_frame)
3542 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
3543 1 /* is_nolookup */ );
3547 VLIB_REGISTER_NODE (tcp4_input_nolookup_node) =
3549 .name = "tcp4-input-nolookup",
3550 /* Takes a vector of packets. */
3551 .vector_size = sizeof (u32),
3552 .n_errors = TCP_N_ERROR,
3553 .error_strings = tcp_error_strings,
3554 .n_next_nodes = TCP_INPUT_N_NEXT,
3557 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3558 foreach_tcp4_input_next
3561 .format_buffer = format_tcp_header,
3562 .format_trace = format_tcp_rx_trace,
3567 VLIB_REGISTER_NODE (tcp6_input_nolookup_node) =
3569 .name = "tcp6-input-nolookup",
3570 /* Takes a vector of packets. */
3571 .vector_size = sizeof (u32),
3572 .n_errors = TCP_N_ERROR,
3573 .error_strings = tcp_error_strings,
3574 .n_next_nodes = TCP_INPUT_N_NEXT,
3577 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3578 foreach_tcp6_input_next
3581 .format_buffer = format_tcp_header,
3582 .format_trace = format_tcp_rx_trace,
3586 VLIB_NODE_FN (tcp4_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3587 vlib_frame_t * from_frame)
3589 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
3590 0 /* is_nolookup */ );
3593 VLIB_NODE_FN (tcp6_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3594 vlib_frame_t * from_frame)
3596 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
3597 0 /* is_nolookup */ );
3601 VLIB_REGISTER_NODE (tcp4_input_node) =
3603 .name = "tcp4-input",
3604 /* Takes a vector of packets. */
3605 .vector_size = sizeof (u32),
3606 .n_errors = TCP_N_ERROR,
3607 .error_strings = tcp_error_strings,
3608 .n_next_nodes = TCP_INPUT_N_NEXT,
3611 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3612 foreach_tcp4_input_next
3615 .format_buffer = format_tcp_header,
3616 .format_trace = format_tcp_rx_trace,
3621 VLIB_REGISTER_NODE (tcp6_input_node) =
3623 .name = "tcp6-input",
3624 /* Takes a vector of packets. */
3625 .vector_size = sizeof (u32),
3626 .n_errors = TCP_N_ERROR,
3627 .error_strings = tcp_error_strings,
3628 .n_next_nodes = TCP_INPUT_N_NEXT,
3631 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3632 foreach_tcp6_input_next
3635 .format_buffer = format_tcp_header,
3636 .format_trace = format_tcp_rx_trace,
3640 #ifndef CLIB_MARCH_VARIANT
3642 tcp_dispatch_table_init (tcp_main_t * tm)
3645 for (i = 0; i < ARRAY_LEN (tm->dispatch_table); i++)
3646 for (j = 0; j < ARRAY_LEN (tm->dispatch_table[i]); j++)
3648 tm->dispatch_table[i][j].next = TCP_INPUT_NEXT_DROP;
3649 tm->dispatch_table[i][j].error = TCP_ERROR_DISPATCH;
3652 #define _(t,f,n,e) \
3654 tm->dispatch_table[TCP_STATE_##t][f].next = (n); \
3655 tm->dispatch_table[TCP_STATE_##t][f].error = (e); \
3658 /* RFC 793: In LISTEN if RST drop and if ACK return RST */
3659 _(LISTEN, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3660 _(LISTEN, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_ACK_INVALID);
3661 _(LISTEN, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_INVALID_CONNECTION);
3662 _(LISTEN, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3663 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3664 TCP_ERROR_ACK_INVALID);
3665 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3666 TCP_ERROR_SEGMENT_INVALID);
3667 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3668 TCP_ERROR_SEGMENT_INVALID);
3669 _(LISTEN, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3670 TCP_ERROR_INVALID_CONNECTION);
3671 _(LISTEN, TCP_FLAG_FIN, TCP_INPUT_NEXT_RESET, TCP_ERROR_SEGMENT_INVALID);
3672 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3673 TCP_ERROR_SEGMENT_INVALID);
3674 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3675 TCP_ERROR_SEGMENT_INVALID);
3676 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3678 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_DROP,
3679 TCP_ERROR_SEGMENT_INVALID);
3680 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3681 TCP_ERROR_SEGMENT_INVALID);
3682 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3683 TCP_ERROR_SEGMENT_INVALID);
3684 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3685 TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3686 /* ACK for for a SYN-ACK -> tcp-rcv-process. */
3687 _(SYN_RCVD, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3688 _(SYN_RCVD, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3689 _(SYN_RCVD, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3691 _(SYN_RCVD, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3692 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3694 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3696 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3697 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3698 _(SYN_RCVD, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3699 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3701 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3703 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3704 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3705 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3707 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3708 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3709 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3710 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3711 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3712 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3713 _(SYN_RCVD, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3714 /* SYN-ACK for a SYN */
3715 _(SYN_SENT, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3717 _(SYN_SENT, TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3718 _(SYN_SENT, TCP_FLAG_RST, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3719 _(SYN_SENT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3721 _(SYN_SENT, TCP_FLAG_FIN, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
3722 _(SYN_SENT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
3724 /* ACK for for established connection -> tcp-established. */
3725 _(ESTABLISHED, TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3726 /* FIN for for established connection -> tcp-established. */
3727 _(ESTABLISHED, TCP_FLAG_FIN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3728 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3730 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3732 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3733 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3734 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED,
3736 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3737 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3738 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3739 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3740 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3741 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3742 _(ESTABLISHED, TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3743 _(ESTABLISHED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3745 _(ESTABLISHED, TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3746 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
3748 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
3750 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3751 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
3752 _(ESTABLISHED, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3753 /* ACK or FIN-ACK to our FIN */
3754 _(FIN_WAIT_1, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3755 _(FIN_WAIT_1, TCP_FLAG_ACK | TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS,
3757 /* FIN in reply to our FIN from the other side */
3758 _(FIN_WAIT_1, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3759 _(FIN_WAIT_1, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3760 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3762 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3763 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3764 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3765 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3766 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3767 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3768 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3770 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3771 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3772 _(FIN_WAIT_1, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3773 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3775 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3777 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3778 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3779 _(FIN_WAIT_1, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3780 _(FIN_WAIT_1, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3782 _(CLOSING, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3783 _(CLOSING, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3784 _(CLOSING, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3785 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3787 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3789 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3790 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3791 _(CLOSING, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3792 _(CLOSING, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3794 _(CLOSING, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3795 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3797 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3799 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3800 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3801 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3803 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3804 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3805 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3806 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3807 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3808 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3809 /* FIN confirming that the peer (app) has closed */
3810 _(FIN_WAIT_2, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3811 _(FIN_WAIT_2, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3812 _(FIN_WAIT_2, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3814 _(FIN_WAIT_2, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3815 _(FIN_WAIT_2, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3817 _(CLOSE_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3818 _(CLOSE_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3820 _(CLOSE_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3821 _(CLOSE_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3823 _(LAST_ACK, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3824 _(LAST_ACK, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3825 _(LAST_ACK, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3826 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3828 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
3830 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
3831 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3832 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3834 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
3835 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3836 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
3837 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3838 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3839 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3840 _(LAST_ACK, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3841 _(LAST_ACK, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3843 _(LAST_ACK, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3844 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3846 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3848 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3849 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3850 _(TIME_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3851 _(TIME_WAIT, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3852 _(TIME_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3854 _(TIME_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3855 _(TIME_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3857 _(TIME_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3858 /* RFC793 CLOSED: An incoming segment containing a RST is discarded. An
3859 * incoming segment not containing a RST causes a RST to be sent in
3861 _(CLOSED, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_CONNECTION_CLOSED);
3862 _(CLOSED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3863 TCP_ERROR_CONNECTION_CLOSED);
3864 _(CLOSED, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_NONE);
3865 _(CLOSED, TCP_FLAG_SYN, TCP_INPUT_NEXT_RESET, TCP_ERROR_NONE);
3866 _(CLOSED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3871 static clib_error_t *
3872 tcp_input_init (vlib_main_t * vm)
3874 clib_error_t *error = 0;
3875 tcp_main_t *tm = vnet_get_tcp_main ();
3877 if ((error = vlib_call_init_function (vm, tcp_init)))
3880 /* Initialize dispatch table. */
3881 tcp_dispatch_table_init (tm);
3886 VLIB_INIT_FUNCTION (tcp_input_init);
3888 #endif /* CLIB_MARCH_VARIANT */
3891 * fd.io coding-style-patch-verification: ON
3894 * eval: (c-set-style "gnu")